question_answer

If pqr = 1, then find the value of \[\left( \frac{\mathbf{1}}{\mathbf{1+p+}{{\mathbf{q}}^{\mathbf{-1}}}}\mathbf{+}\frac{\mathbf{1}}{\mathbf{1+q+}{{\mathbf{r}}^{\mathbf{-1}}}}\mathbf{+}\frac{\mathbf{1}}{\mathbf{1+r+}{{\mathbf{p}}^{\mathbf{-1}}}} \right)\]

A)  \[pq+qr+rp\]                                        

B)  1

C)  pq + qr                                                           

D)  p/q

E)  None of these