Which material undergoes radioactive decay?

O al elements that have a half life

O all elements that contain atoms with protons

O all elements that have turned into a new element

all elements that have a consistent number of particles

The materials which goes radioactive decay have the following property:

A) All elements that have a half life

Explanation:

Half life is a term commonly used in Radiophysics. It can be defined as the time required for one half of the atomic nuclei of an unstable radioactive elements to decay.

For example the radioactive element Cobalt has a half life of 5.26 years, which means if we have a sample which contains 20 grams of Cobalt initially, after 5.26 years, it will reduce to 10 grams.