GMAT Critical Reasoning (CR) | Re: RAGCT Day 13: Concerns for the environment have led

I did a brief analysis.

We must to have in mind that the correct question must always be true.

Concerns for the environment have led chemists to develop plastics that are degradable. All degradable plastics, which are potentially useful packaging materials, need just the right conditions to break down. Some need exposure to sunlight, some need to be buried in soil, and some need to be submerged in water. It should be cautioned that some degradable plastics leave residues of unknown toxicity.
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