Mutations that neither benefit nor harm the organism have effect on the organism's survival.

false

Explanation: because it mutation can help or not help in many ways think of a mocking bird if its beck was short it would have a less chance of surviving. if the mockingbird had a longer beck it would surviving .This leads up to natural selection.  

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.