Self-study
Support Thirty years ago, the percentage of their income that single persons spent on food was twice what it is today. █████ ████ ███████ ████ █████ ████ ███ ████ ██████ ██████ ██ ███ ████████ ████ ███████ ████ █████ ██ █ ███████ ████ ████ ███ █████ ██ ████ ██ ████ ███████
Summary
Incomes today are higher than they were 30 years ago, and 30 years ago single people spent a higher percentage of their income on food than people do today. Therefore, incomes have increased faster than food prices over the past 30 years.
Notable Assumptions
The argument moves from a statement about how much people spend on food over time to a conclusion that the change in spending is because of a change in the cost of food items. It doesn't, however, explicitly state that single people kept buying the same exact food over those years. It’s still possible that the reason single people spend less of their income on food today is because they’re eating less or because they’re eating cheaper foods. We’re therefore looking for some assumption that helps justify the conclusion by ruling out possible alternative explanations of the trend.
21.
Which one of the following, ██ ████████ █████ ████ ██ ███████ ███ ██████████ █████ ██████
a
The amount of ████ █████ ███ ██████ █████ ██ █████████ ██ ███ ██████ ██ ████ █████ ███ ██████ ██████ █████ ████
Wrong trigger. This answer discusses food eaten per capita, whereas the argument is specifically about the amount of money spent on food by single persons.
b
In general, single ███████ █████ ███ █████████ █████ ███ ███ ████ ████ █████ ████████████ ██ ██████ █████ ████
Undermines the argument. If single persons today eat less, that would be an alternative explanation for why they spend less on food - it would not necessarily be because the price of food increased slowly.
c
Single persons today, ██ ████████ ████████ ███ ████ █████ ██ ████ █████ ██ ███ ████ ██████████ ██ ████ ███ ██████ █████ ████
This would rule out the possible alternative explanations of the trend and therefore would help justify the conclusion.
d
The prices of ███████ █████ ██████ ███████ ████████ ████ █████ ██████ ████ ███ █████ ██ ████ ████ ███ ████ ██████ ██████
The argument isn’t about nonfood items, and an assessment of their price does nothing to help the argument.
e
Unlike single persons, ████████ █████ █████ █████ ███ ████ ██████████ ██ █████ ██████ ██ ████ ██ ████ ███ ██████ █████ ████
The argument isn’t about family purchases, and an assessment of their costs and income does nothing to help the argument.