Answer: Option (b) is the correct answer.
Step-by-step explanation:
A nuclear particle which is positively charged is known as an alpha particle. An alpha particle is emitted during a radioactive decay.
Mass of an alpha particle is similar to mass of a helium atom, that is why, a helium atom is also known as an alpha particle.
Therefore, an alpha particle is denoted as
. That is, there are 2 protons and 2 neutrons in an alpha particle.
Thus, we can conclude that an alpha particle is identical to the nucleus of a helium atom.