If `vec a, vec b, vec c` are non coplanar vectors such that, `vec b xx vec c = vec a, vec c xx vec a = vec b, vec a xx vec b = vec c`, then |vec a + vec b + vec c| = `

Options

A. `p = vec a . vec a vec r = (vec a xx vec b)`
B. `p = vec b . vec a , vec r = vec a xx vec b`
C. `p = vec a . vec a , vec r = vec b xx vec a`
D. `p = vec b . vec b, vec r = vec b xx vec a`

Answer

C