Tissue engineering and stem cells:

answer:

i believe the answer is d).

explanation:

i think this is because you are tearing apart the muscle, and then when you eat, the muscle re-heals, making itself even stronger.

edit: i put b) before but i meant to put d). sorry for the incorrect answer.

the worst joke is

hey wanna hear a pencil joke

nevermind its pointless

answer:

it could come from a variety of sources.

explanation:

..although it was most likely developed through zoonotic transmission, where an infectious disease which usually afflicts when animals jump to humans.

i know it happens all the time :