In a few generations, this population of beetles changed. A group of bugs includes 13 black bugs and 4 green bugs. After a few generations, there are 13 green bugs and 4 black bugs.

Which is the most likely explanation for the change?
The beetle population moved to a greener habitat.
A natural disaster almost caused the extinction of the population.
The beetle population’s food sources decreased dramatically.
A mutation resulted in a new color of insect.

The beetle population moved to a greener habitat.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.