An infinitely long conductor is bent into a circle as shown in figure. It carries a current I ampere and the radius of loop is R metre. The magnetic induction at the centre of loop is
A. `(mu_(0)2I)/(4piR)(pi + 1)`
B. `(mu_(0)2I)/(4piR)(pi - 1)`
C. `(mu_(0)I)/(8piR)(pi + 1)`
D. zero