Atoms of the least reactive elements tend to have a. one or seven valence electrons. b. eight valence electrons. c. four or five valence electrons. d. no valence electrons

Option (B) is the correct answer.

Explanation:

When an atom's octet or shell is filled then the atom becomes stable. Therefore, the atom will be very less reactive as it does not need more electrons to fill its shell.

For example, neon has atomic number 10 and electron distribution in its shells is 2, 8. As there are 8 electrons in its valence shell this means that it has attained stability according to the octet rule. Hence, it will be least reactive.

Thus, we can conclude that atoms of the LEAST reactive elements tend to have eight valence electrons.