Rubidium ${ } _ { 37 } ^ { 87 } \mathrm { Rb }$

Multiple Choice

Rubidium ${ } _ { 37 } ^ { 87 } \mathrm { Rb }$ is a naturally occurring isotope that undergoes $\beta ^ { - }$ decay. What isotope is the product of this decay?

A) ${ } _ { 38 } ^ { 87 } \mathrm { Sr }$
B) ${ } _ { 37 } ^ { 87 } \mathrm { Rb }$
C) ${ } _ { 38 } ^ { 87 } \mathrm { Kr }$
D) ${ } _ { 36 } ^ { 87 } \mathrm { Sr }$
E) ${ } _ { 36 } ^ { 87 } \mathrm { Kr }$