Complete the Following Nuclear Decay Reaction ${ }_{88}^{221} \mathrm{Ra} \rightarrow+{ }_{2}^{4} \mathrm{He}$

Multiple Choice

Complete the following nuclear decay reaction. ${ }_{88}^{221} \mathrm{Ra} \rightarrow+{ }_{2}^{4} \mathrm{He}$

A) ${ }_{86}^{217} \mathrm{Rn}$
B) ${ }_{88}^{217} \mathrm{Ra}$
C) ${ }_{92}^{217} \mathrm{U}$
D) ${ }_{86}^{225} \mathrm{Rn}$
E) ${ }_{90}^{225} \mathrm{Th}$