Answer:
The correct answer is:
Getting enough protein is a common concern for vegetarians.
Step-by-step 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 fulfil all the protein needs, he says, he just pays special attention in order to find the correct balance in his diet.