In A, stronger may not be the good word, but if a species needs to get stronger to survive then it will get stronger through natural selection.
B This in my opinion is true because the species will always adapt to what traits it needs to survive and this ties in with D becuase D is very similar
C causes changes in population in my opinion is the least likely to be true, this is because natural selection only effects offspring and not current population, which is why I would consider this one to be false.
To be honest I'm not sure this is a very tough question and is worded strangely. I would choose C or A, I would suggest getting a second source
