Which training principle states that exercising a certain body part or practicing a particular skill primarily develops that part or skill?

konichiwa~! my name is zalgo and i am here to you out on this amazing day. i have been through break-ups before, and they are not easy. each one seems to get a bit harder yet easier. the best thing to do is do the things you enjoy doing the most before you had got in t he relationship. maybe even try and find new and more exciting things to do that will take your mind off of it. and it is no surprise you seem to have a fear to talk to anyone, most people do, it's called "anxiety". most people overcome and conquer their anxiety. just try talking to someone on a video game or go out to a coffee shop and try starting a conversation with a person. that will definitely !

i hope this ! : 3

"stay and stay proud! " - zalgo

i think it would be b the increase in body temp

d would be your answer