Answer:
False
Explanation:
According to the laws of radioactive decay, when an atom undergoes an alpha decay, the mass number is decreased by 4 units and atomic number is decreased by 2 units .
[tex]X_{Z}^{A}\overset{\alpha decay}{\rightarrow}Y_{Z-2}^{A-4}[/tex]
Thus, it is false, as the atomic number is decreased by 2 units only.