The fact that the relative abundance is greater for elements in which the total number of protons and neutrons is a multiple of two is because __________.

of the four nuclear decay processes only the α-decay changes the number of protons

conservation of baryon number favors processes involving two protons

of the four nuclear decay processes only the α-decay changes the baryon number and does so in increments of four

the combination of two protons and two neutrons is very stable