Self-study
Columnist: Conclusion The advent of television helps to explain why the growth in homicide rates in urban areas began significantly earlier than the growth in homicide rates in rural areas. ██████████ ████ ██████ ███████ ██ █████ ██████████ █████ ████ █████ ███████ ████ ██ █████ ███████████ █████ ████████ █████ █████ ██████████ ██ █████ █████ ████ █████ ███████ ████ █ ███████ ████████ ██ █████ ████████ █████ ██████
Phenomenon-Hypothesis
The phenomenon, i.e. facts, are these: television sets became popular in urban households five years before they were popularized in rural households. Urban homicide rates also started growing in 1958, four years before rural homicide rates saw a similar increase. The columnist hypothesizes that the advent of television helps explain why homicide rates in urban areas began growing before homicide rates in rural areas.
Notable Assumptions
This is a seriously flawed argument. You might immediately start thinking along the lines of a classic correlation/causation flaw pattern, since the columnist doesn't even consider that the growth in urban homicide rates might have begun earlier than the growth in rural homicide rates based on other causes, besides the advent of TV.
But even more egregiously, the author doesn't even show that the advent of TV is even correlated to the growth in homicide rates, because she doesn't show that those phenomena occurred at the same time, let alone that TV arrived before homicide rates went up. We know that TV came to urban households "about five years" earlier than to rural households, and that growth of urban homicide rates began "about four years earlier" than similar growth in rural areas. But while these are similar durations of "lag" between urban and rural areas, we're given a specific date for when the growth of urban homicide rates began — 1958 — and we aren't given any dates for when TV came to urban households.
So, for all we know, it's possible that TV came to urban households later than 1958, in which there's no way the advent of TV would help explain anything about the growth in homicide rates. This is a gaping hole in the argument, which argues purely from similarities in the duration of "lag" between urban and rural areas, without establishing that those periods of lag overlapped with each other.
But even though this is a really big flaw in the argument, remember that an answer choice that addresses only this flaw — i.e., that tells us that the advent of TV in urban areas occurred just prior to the growth of homicide rates in those areas, and likewise for rural areas — would still only establish that these phenomena are correlated, not causally linked. An ideal answer choice would both show that these phenomena are correlated (i.e., that they occurred in overlapping periods) and establish a causal link between increased access to TV and homicide rates going up.
18.
Which one of the following, ██ █████ ████ ████████ ███ ███████████ █████████
a
In places where ███ ██████ ██ ███████ ██████████ ████████ ██ ████ ███ ████████ █████ ███ ████ ████
You might be tempted to pick this answer choice because it seems to address the most glaring flaw in the argument: that the argument doesn't even establish a correlation between TV and homicide rates. Even if this answer choice did establish such a correlation in a way relevant to the argument, we would still be left with an argument that argues for causation from correlation alone — but you would be right to think that this would at least be a contender for a strengthening answer choice.
Crucially, however, this answer choice doesn't even establish the correlation we're interested in. It establishes a correlation between violent TV programs and homicide rates in "some areas," but doesn't establish that the presence of television sets (the physical object) in urban vs. rural areas correlates with the specific spike in urban vs. rural homicide rates discussed in the stimulus, let alone show that the advent of TV was causally linked to that spike. So this doesn't strengthen the argument at all.
b
The portrayal of ████████ ██ ██████████ ██ █ ██████ ███ ██ ███████ ██ ███ ████████ ██ ████████
This strengthens the argument by providing a causal mechanism that links television sets to homicide rates. If violence on TV is in fact a cause of violence in society, and not the other way around, this would show how the advent of TV explains the rise in homicide rates beginning earlier in urban areas than in rural ones, since TV came to urban areas earlier than rural ones.
You might notice that this assumes that TV came to urban areas before 1958, when homicide rates went up in those areas, and likewise for rural areas. And you would be right — this answer choice doesn't fix what might seem to be the most obvious flaw in the argument. But it does strengthen one aspect of the argument regardless: it's possible to strengthen a flawed argument without making it bulletproof. So this is the answer choice we want.
c
There were no ███████ ██████████ ████████ ██████ ███ █████ █████ ██ ███████████
This doesn't strengthen the argument. It doesn't address any of the flaws we identified: we still don't know if the advent of TV was earlier than the rise in homicide rates, let alone causally linked to those rates. Even if we assume the first fact, that the advent of TV was prior to the rise in homicide rates, this answer choice would seem to weaken the argument, not strengthen it, because it tells us the first few years of TV didn't have any violent TV shows that might have prompted the rise in homicide rates.
d
The earlier one ██ ███████ ██ ████████ ██ ███████████ ███ ████ ████████ ███ ███████
This is irrelevant. It doesn't address any of the flaws in the argument, which isn't about the age when people were exposed to television, but about the timeframe when TV was introduced to certain places. And this answer choice doesn't specify what "effect" it's talking about. So this is completely unrelated to the argument.
e
Increasing one's amount ██ ███████ ████ █████████ █████ ███████████ ██ ███ ██████████
This is also irrelevant. The argument doesn't tell us anything about leisure time. To assume that the popularization of TV necessarily indicates an increase in leisure time, and therefore potentially explains a rise in violence, would be to make an assumption that goes beyond the stimulus.