They produce saliva which is essential for the breaking down of carbohydrates.
An athlete would have a larger vital capacity than a non-athlete aerobic ability would find people with larger lungs and hence a bigger vital capacity. The vital capacity of an athlete is higher than a non-athlete because they are trying to do hard work their legs to get bigger and bigger over time making it easier for them
The answer is A hope this helped you :)<span />
A and D seem like the best answers
