Charge on a body is quantized which means the charge on the body will be an integral multiple of e.
Step 2: Check whether n is an integer or not
Equation (1)⇒4.8×10−20C=n×1.6×10−19C
⇒n=4.8×10−201.6×10−19=0.3
0.3 is not an integer. Therefore, a body can't have a charge of 4.8×10−20C.
Hence, Option(B) is correct.