Study the Body of Each of the Following Paragraphs

Study the body of each of the following paragraphs. Then, select the letter of the topic sentence that is most accurate. Select the best topic sentence for the paragraph.
A study conducted by George Washington University and the National Endowment for the Arts showed that senior citizens who sing in a choir are physically healthier than senior citizens who aren't involved in an arts program. Plus, the singers are less likely to suffer from depression and mental deterioration. Dr. Graham Welch of the University of Surrey, who has spent over thirty years researching the effects of singing, claims that singing requires breathing deeply, so it's good aerobic exercise for the lungs, abdominal muscles, and circulatory system. Physician Eric Roter, who reviews the connection between music and health on his web site ermusic.org , agrees. He says that when people sing, the body responds as though it was getting a physical workout. Plus, singing just makes people feel good. Research from Manchester University suggests that singing stimulates a small organ in the inner ear called the saccule, which produces pleasure. Also, endorphins released during singing relax the body and lift the singer's spirits.

A) Singing in a choir is a lot of fun.
B) Singing appears to benefit physical and mental health.
C) Music is a very important part of life.