The Distance Between $P _ { 1 } = ( 3,2,6 )$

The distance between $P _ { 1 } = ( 3,2,6 )$ and $P _ { 2 } = ( - 1,2,5 )$ is

A) $\sqrt { 13 }$
B) $\sqrt { 15 }$
C) $\sqrt { 17 }$
D) $\sqrt { 19 }$
E) $\sqrt { 21 }$