Which type of radiation is the smallest in size?

alpha radiation

beta radiation

gamma radiation

positron radiation

Positron radiation

The increasing order of the size of radiation is as follows: Positron Radiaiton < Beta Radiaiton < Alpha Radiaiton

Alpha radiations are the slowest because of their size and so they are not able to penetrate into the matter. And, positron radiations are the fastest and can penetrate really well.

Note: Gamma radiations are the fastest and most penetrating but they are not matter but energy.