Calculate the Value Mentally $\frac { 12 ^ { 1 / 2 } } { 3 ^ { 1 / 2 } }$

Calculate the value mentally.
- $\frac { 12 ^ { 1 / 2 } } { 3 ^ { 1 / 2 } }$

A) 2
B) none of these
C) 9
D) 4