Which of these is the correct answer?

Asmall number of finches are removed randomly from the wild and placed in a protected bird area. they are given as much food as they need and have plenty of space. why would natural selection not occur in this population? a. there is no reason for genetic mutation to occur. b. the birds compete for limited resources, c. the population has not reached carrying capacity. d. there is no genetic variation in the finches.

What is thought to have caused the mass extinction at the end of the cretaceous period?

What are the formed elements (cell or parts of cell) in blood and what are their functions ?