What is the difference between individualization and specificity? This is P. E but they don't have that option

The principle of individualization is that no two people are the same. ... The principle of specificity is that exercising a certain body part or a particular skill primarily develops that part or skill.

Answer d would be the best answer, for he wants to have part in biotechnology. an ekg technician is quite similar.

Well if you pick a machine to work on and that's gonna be your exercise if you don't stick to that machine your muscle strength your muscle mass rather will change because you haven't been doing it you change something in your exercise routine which changes your body's form of dealing with things for example you might become weaker or stronger depending on what kind of exercises you do in whether or not the machine you picked actually your muscles grow.