Answer:
A. It increases the number of protons
Step-by-step explanation:
When alpha radiation is emitted by a particle, its number of protons decrease by two, that is, the particle lost two protons.
Option B is true because alpha particle is composed by 2 protons and 2 neutrons.
Option C is true because a change in the structure of atomic nuclei of the parent particle is produced.
Option D is correct because alpha radiation is heavier than beta and gamma radiations.