Suppose that a plant disease kills all the fruit. The change could become a
on
the birds

selective pressure

Explanation:

selective pressure means a cause that reduces success in ones portion or/of a population so that can be the same for bird if a plant disease found its way to a plant the a bird eats.

the answer is c) an oak tree

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .