When $\begin{array} { c } 218\\84\end{array}$ Po Emits a Beta Particle,it Transforms into a New Element

Multiple Choice

When $\begin{array} { c } 218\\84\end{array}$ Po emits a beta particle,it transforms into a new element.What are the atomic number and atomic mass of this new element?

A) atomic number = 84; atomic mass = 219
B) atomic number = 86; atomic mass = 214
C) atomic number = 85; atomic mass = 218
D) atomic number = 82; atomic mass = 214