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.

the answer is c) an oak tree

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.