Due to which force are beta (β) rays, or electrons, emitted from a radioactive nucleus?

Think it through first, then pick an option.

Answer and explanation

Correct answer: b weak nuclear force

Beta rays, or electrons, leave a radioactive nucleus because of the weak nuclear force.

Why the other options are wrong

a magnetic force: The magnetic force is one face of the electromagnetic force; it is not what lets beta rays out.
c electric force: The electric force is part of the electromagnetic force; the book names the weak nuclear force as the cause of beta rays.
d strong nuclear force: The strong nuclear force holds protons and neutrons in the nucleus; it does not emit beta rays.