Abeta particle may be spontaneously emitted from
(1) a ground-state electron
(2) a stable nucleus
(3) an excited electron
(4) an unstable nucleus

Answer;

-Unstable nucleus

Explanation;

A beta particle may be spontaneously emitted from an unstable nucleus. Unstable nuclides undergo spontaneous change or radioactive decay by emitting radiations to attain stability. These radiations are, alpha (α)radiation, beta (β) radiation or gamma (γ) radiation.

2b2t

explanation:

2b2t