Self-study
All laundry detergents contain surfactants, which can harm aquatic life. ████████ ███ █████████████ ███████ ██ ████ ███████████ ██ ███████ ███████████ █████████ ████ ██ █████ ██ █████████ █████████████ █████████ ███████████ ███ ████████ ██████████ █████ ██ ██ ██████ ██ ███████ ████ ███████ ██████████ ██████████ ██ ████████████ ████████ ███ ████ ████████ ██ ███ ███████████ ████ █████ ███████ ██████████ ████
Summarize Argument
The author concludes that there is no reason to believe that laundry detergents advertised as “eco-friendly” are less damaging to the environment than other laundry detergents are. He supports this by saying that the environmental effects of most laundry detergent ingredients, including most ingredients in “eco-friendly” detergents, are unknown.
Notable Assumptions
The author assumes that because the environmental effects of most detergent ingredients are unknown, there is no reason to believe that "ecologically friendly" detergents are less damaging. This ignores the possibility there could be some other reason to believe that eco-friendly detergents are less damaging, such as the effects of those ingredients that are known, or the effects of some other factor like packaging or production.
9.
Which one of the following, ██ █████ ████ ███████ ███ █████████
a
Laundry detergents that ███ ██████████ ██ ████████████ ████████ ███████ ████ █████ ███████ ██ ████████████ ██ ████████ ████ ██ █████ ███████ ███████████
If “eco-friendly” detergents contain much lower amounts of environmentally damaging surfactants than other detergents, this gives a reason to believe that they might be less damaging to the environment, even though the effects of most of their ingredients are unknown.
b
There is no ██████ ██ ███████ ████ ████ ██ ███ ███████████ ██ ███████ ██████████ ███ ██████████ ██ ████████████ ████████ ████ ███ ███████████ ██████████████
The columnist’s argument is about the environmental effects of those detergents that are advertised as eco-friendly. Whether or not there is reason to believe that regular laundry detergents harm the environment doesn’t weaken her conclusion about “eco-friendly” detergents.
c
Different kinds of ███████ ██████████ ███████ █████████ █████ ██ ████████████ █████ ██████ ██ ███ ██████ ██ █████ ████ █████ ███████████ ████ ███████ █████
This is too vague to weaken the columnist’s conclusion because we don’t know which kinds of detergents contain which kinds of surfactants. Do “eco-friendly” detergents contain more harmful or less harmful surfactants? (C) doesn’t give us this information.
Unwarranted assumption
Unwarranted assumption
d
There is reason ██ ███████ ████ ███████████ ██ ███████ ██████████ █████ ████ ███████████ ████ ███ ███████████ ████ ████ ███████████ ███
Like (C), this is too vague to impact the columnist’s argument. We don’t know which detergents contain these other, more harmful ingredients, so we can’t conclude anything about the effects of “eco-friendly” detergents.
e
Laundry detergents advertised ██ ███████████████ ████████ ███ █████████ ████ █████████ ████ █████ ███████████ ██ ████ ██████ ███████ ████ ██ █████
If larger amounts of “eco-friendly” detergents must be used and these detergents contain harmful surfactants, (E) strengthens the columnist’s conclusion that there is no reason to believe that “eco-friendly” detergents are less damaging to the environment than other detergents.