It would be A because when you are younger you want to have a higher heart rate while working out.
Im sure it is c because the first two are wrong for sure and c is probably right because people with mild gad usually dont avoid certain situations even though its very difficult for them
d is wrong because its been proven that you can get gad and all of that if family members also have it so i doubt this is the correct answer
As many as it takes to complete the goal.