Answer:
Harmful mutations don't accumulate over time because they reduce the reproductive success of an organism! These mutations would be dead before they can produce any offspring, so there's a slim chance of their genes being passed on. (So it's basically like survival of the fittest, the ones that survive usually have beneficial mutations because that's what keeps them alive lol) Beneficial mutations play a big role in evolution too!
Step-by-step explanation:
I hope that cleared things up for you! pls give me brainliset <3