What types of variation are frequently exhibited in a population or species ?

The variety of alleles in a population, resulting in a variety of phenotypes. Important to help survival of species in an changing environment.

Explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds