Question

There are more hydrogen atoms in living organisms than any other atom, but oxygen is more abundant in terms of mass.

Answer 1

The right answer is B.

*Hydrogen is the most abundant element representing nearly three quarters of the mass of the universe.

*Hydrogen is found in the water that covers 70% of the surface of our planet as well as in all organic matter.

*Hydrogen is the simplest element in the universe. It is composed only of one proton (p) and only one electron (e-).

*Hydrogen is the lightest element of all elements and gases; it is 14 times lighter than air. A "spill" of hydrogen gas immediately diffuses into the air and pollutes neither the ground nor the water table.

*Hydrogen is invisible, odorless and nontoxic. It does not cause acid rain, does not deplete the ozone layer and does not generate dangerous emissions.

Answer 2

Hydrogen has a much much smaller mass.  Oxygen is like 16 times more dense.