Astable atom that has a large nucleus most likely contains
more neutrons than protons.
more protons than neutrons.
equal numbers of protons and neutrons.
changing numbers of protons and neutrons.

Option (a) is the correct answer.

Explanation:

It is known that ratio of neutron is to proton is equal to 1.5.

Mathematically,              

This means that in a large nucleus there will be 2 protons for 3 neutrons. That is, the number of neutrons will always be slightly greater than the number of protons.

Hence, we can conclude that a stable atom that has a large nucleus most likely contains more neutrons than protons.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).