HELP 15 POINTS The main function of the respiratory system is .

A) the carrying of nutrients to body cells
B) the exchange of gases between the body and the environment
C) the prevention of diseases caused by pathogens
D) the elimination of wastes from the body

D) the elimination of wastes from the body

i think that d. wind is the answer.   i missed the question when i answered a. currents.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.