Two boys are standing at the ends A and B of a ground, where `AB=a`. The boy at B starts running in a direction perpendicular to AB with velocity `v_(1)`. The boy at A starts running simultaneously with velocity v and catches the other boy in a time t, where t is :

Options

A. a//sqrt(v^2+v_1^2`
B. sqrt(a^2//(v^2-v_1^2)`
C. `a/(v-v_1)`
D. `a/(v+v_1)`