Consider $\;\alpha\;, \beta \;, \gamma\;$ rays each having an energy 1 MeV . Arrange them in increasing order of penetrating powers of radiation.

Question

$(a)\;\alpha , \beta , \gamma\qquad(b)\;\beta , \gamma , \alpha\qquad(c)\;\alpha , \gamma , \beta \qquad(d)\;\gamma , \beta , \alpha$