Self-study
Consumer advocate: In some countries, certain produce is routinely irradiated with gamma rays in order to extend shelf life. █████ ████ ████████ ████ ███████ ██ █████ ██████████ ██████ ██████ ████ ███ ███████ ██ ███ ███████████ ██████████ ████ ███████ ███ █████ █████ ███████ ███████████ ███ ██████ ███ ███████ ███████ ██ █████ ██████ ███████ ██████ ███████ ████████ █████████ ██████ ███████████ ██████ ██████ ██████████ ████████ ████ █████ ███████ ██████ █████████ █████████ ███████
Summarize Argument
The author concludes that irradiated foods should be avoided, based on three points: (1) they are exposed to radioactive substances, (2) irradiation can reduce vitamins and leave harmful chemical residues, and (3) irradiation creates unique radiolytic products that may cause serious health issues, including cancer.
Notable Assumptions
The author assumes that avoiding irradiated foods is overall better than eating them. He ignores any positive effects of irradiation and assumes the following negative effects:
Irradiation causes unique radiolytic products to be in the produce itself.
Just because irradiation can reduce vitamins, it does reduce them.
The amount of harmful chemical residue left after irradiation is more than the amount left without it.
Because irradiation creates radiolytic products which cause cancer, irradiated foods cause cancer.
19.
Each of the following, if █████ ███████ ███ ████████ ██████████ ████████ ███████
a
Unique radiolytic products ████ ██████ ████ █████ ██ ███ ██████████ █████
The consumer advocate assumes a negative effect of radiation— namely, that irradiation, which creates unique radiolytic products, causes those products to be present in the produce itself. (A) weakens the argument by showing that this assumption is false.
b
Cancer and other ███████ ██████ ████████ ████ ████ ██████ ████ ███ █████████ ██ ███████████ ██████████ ███ █████ █████
This doesn't weaken the argument. The fact that cancer and other health problems have other causes doesn't mean that radioactive substances and gamma rays don't also cause these issues. Also, (B) doesn’t address the assumption that irradiated foods cause these problems.
c
A study showed ████ ███████████ ██████ ███ ███████ ███████ ██ █████████ ███ ██████ ███ ██████████ ██████████
The consumer advocate assumes that, just because irradiation can reduce the vitamins in produce, it does reduce the vitamins in produce. (C) weakens the argument by showing that this assumption is false and that irradiation actually keeps the vitamin content intact.
d
The amount of ███████ █████████ █████ ██ ██████████ █████ ██ ████ ████ ███ ██████ ████ ██████ █████████ ██ ████ █████ ██ ██████
(D) weakens the argument by pointing out a positive effect of irradiation: irradiated foods have fewer harmful chemicals than most non-irradiated foods. It also shows that the assumption that irradiation leaves produce with more harmful chemicals is false.
e
A study showed ████ ███ ██████ ████ ██ ██ ██████ █████ ██████ ███ ███ ██████████ ████ ████ █████ █████ ███ ██ ████
The consumer advocate assumes that, because irradiation creates unique radiolytic products and these products cause cancer, irradiated foods cause cancer. (E) undermines this link by showing that cancer rates are not actually higher among people who eat irradiated food.