Answer: D) it usually accompanies beta or alpha radiation..
Explanation:-
Gamma decay : In this process, the unstable nuclei transformed into stable nuclei by releasing gamma rays along with beta or alpha decay. It is observed when a nucleus is formed in an excited state and then decays to its ground state by emitting an electromagnetic radiation.
General representation of an element is given as:
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
General representation of gamma decay :
