Why Do Some Countries Abstain from Acquiring Nuclear Weapons

Why do some countries abstain from acquiring nuclear weapons?

A) Most countries cannot afford to purchase nuclear weapons.
B) The technology for making nuclear weapons is too difficult for most countries to obtain.
C) The materials for making nuclear weapons are too difficult for most countries to obtain.
D) Countries use alternative methods to ensure their security rather than obtain nuclear weapons.
E) Countries have moral objections to possessing nuclear weapons.