A radioactive nucleus gives out either an $\alpha$-particle or a $\beta$-particle. What products result from these two kinds of radioactive emission?
- Aafter $\alpha$-emission: a nucleus of a different element; after $\beta$-emission: a nucleus of a different element
- Bafter $\alpha$-emission: a nucleus of a different element; after $\beta$-emission: a nucleus of the same element
- Cafter $\alpha$-emission: a nucleus of the same element; after $\beta$-emission: a nucleus of a different element
- Dafter $\alpha$-emission: a nucleus of the same element; after $\beta$-emission: a nucleus of the same element