The essential distinction between `X` - rays and `gamma` - rays is that

Options

A. `gamma` - rays have smaller wavelength than `X` - rays
B. `gamma` - rays emanate from nucleus while `X` - rays emanate from outer part of the atom
C. `gamma` - rays have greater ionizing power than `X` - rays
D. `gamma` - rays are more penetrating than `X` - rays

Answer

B

Explanation

The wavelength of the `gamma` - rays is shorter . However the main distinguishing feature is the nature of emission.