A cytotoxic T cell recognizes and destroys cells infected by a virus. They are also responsible for killing cancer cells too.
Cellular differentiation is the process in which a cell changes from one cell type to another. Usually, the cell changes to a more specialized type. Differentiation occurs numerous times during the development of a multicellular organism as it changes from a simple zygote to a complex system of tissues and cell types. So I believe the answer you are looking for would be the third one :)
Hope this helps! Please let me know if I'm wrong :)
Gene pool would be the most logical answer.
Answer:
It's B: equilateral and isoscleles Explanation: both those words mean triangle with equal sides :)