Option B i.e Financial Problems is the correct answer.
Metabolism (Conversion of food into energy), childhood obesity (over-weight) and medical problems (disease or other health problem) are directly related to child's health and thus influences his body composition. On the other hand, a child does not have any financial problems or financial pressure and thus does not influence his body composition.
I attached a PFD with the answer to your question and roughly 50 others involving acceleration and how to calculate it. This PDF gives you the answers to all the question whilst showing you an in-depth explanation on how they got the answer. Hopefully that helps
