Difference between high school biology and college biology

There is more to remember yes. But as you go into higher levels of biology, the focus is usually going to shift more towards molecular biology. Also the content is going to get more detailed and specific, knowing specific names of receptors, etc.

a, i am pretty sure.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".