Which is a major contributor to the success of our species? a. human adaptability b. high fecundity c. skin tone variation d. body variation?

Answer is (a) human adaptability.

Rationale for rejecting b,c,d options:

Humans do not have a high fecundity, they can give birth to 1-3 offspring on an average.

The skin tone variation is an adaptation that is based on the geography. The sunlight intensity affects it. It is a part of the ability of the humans to efficiently adapt to their surroundings.

The body variation in the form of physical features is also the result of the ability of the humans to adapt to their surroundings.

every el niño cycle is different. every year.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.