`beta` decay means emission of electron from

Options

A. innnermost electron orbit
B. a stable nucleus
C. outermost electron orbit
D. radioactive nucleus.

Answer

D

Explanation

In beta minus (`beta^(-1)`) decay, an eletron is emitted by the radioactive nucleus, as in the decay
`""_(15)^(32)Pto""_(16)^(32)S+""_(-1)e^(0)+barv`
where `bar(v)` is the antineutrino.
In beta plus `(beta^(+))` decay, a positron is emitted by the radioactive nucleus, as in the decay
`""_(11)^(22)Nato ""_(10)^(22)Ne+e^(+)+v`
wehre v is the neutrino.