) Reread the section "Protein Power." Which piece of evidence in this
section conflicts with the author's point of view that meat isn't necessary
in a diet?!!!

The correct answer is:

Getting enough protein is a common concern for vegetarians.

Explanation:

In the text "Protein Power", the author explains how normally vegetarians face some troubles regarding the amount of protein they include in their diet , that has a central rule to avoid the consumption of meat that is the greatest source of protein in a normal diet. Nevertheless, the author explains how, with a little extra effort, it is possible to fulfill all the protein needs, he says, he just pays special attention in order to find the correct balance in his diet.

you should start by saying what they did to these subjects hope that this

a simple sentence must have at least one dependent clause.