The known forces of nature can be divided into four classes, viz, gravity electromagnetism, weak nuclear force and strong nuclear force. with reference to them, which one of the following statements is not correct?
(a)
Gravity is the strongest of the four
(b)
Electromagnetism act only on particles with an electric charge
(c)
Weak nuclear force causes radioactivity
(d)
Strong nuclear force holds protons and nutrons inside the nuclear of an atom.