Answer: The correct answer is option 2.
Explanation:
There are 4 types of decay process, in which a radioisotope can become stable. They are:
1.) Alpha decay: In this process, alpha particles are emitted when a heavier nuclei decays into lighter nuclei. The alpha particle released has a charge of +2 units and has a mass of 4 units. The alpha particle released is also known as helium atom.
[tex]_Z^A\textrm{X}\rightarrow _{Z-2}^{A-4}+_2^4\alpha[/tex]
2.) Beta-decay: In this process, a neutron is converted into a proton and an electron with the release of a beta-particle. The beta particle released carries a charge of -1 units. and it does not have any mass.
[tex]_Z^A\textrm{X}\rightarrow _{Z+1}^A\textrm{Y}+_{-1}^0\beta[/tex]
3.) Gamma ray emission: In this process, an unstable nuclei releases excess energy by a spontaneous electromagnetic process and [tex]\gamma -radiations[/tex] are emitted. These radiations does not carry any charge and are electrically neutral.
[tex]_Z^A\textrm{X}^*\rightarrow _Z^A\textrm{X}+_0^0\gamma[/tex]
4.) Positron decay: In this process, a proton is converted to a neutron and an electron neutrino and positron particles are released. This particle carries a charge of +1 units and does not have any mass. This type of decay is also known as beta-plus decay.
[tex]_Z^A\textrm{X}\rightarrow _{Z-1}^A\textrm{Y}+_{+1}^0e[/tex]
From the above information, gamma decay is represented as [tex]_0^0\gamma[/tex]
Hence, the correct answer is Option 2.
