Scientists may use fossil evidence to support the theory
that domestic dogs are related to wolves. Which of the
following would be considered the most valid evidence
to support the argument that wolves and dogs
descended from a common ancestor?
a. DNA comparisons of dogs and wolves
b. Anecdotal evidence of how dogs and wolves interact
with each other in the wild.
C. Examination of the niche that dogs and wolves fill in
an ecosystem.
d. Mating patterns in dogs and wolves.

Only a. DNA comparisons of dogs and wolves is valid evidence.

Explanation:

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.