Infinite number of straight wires each carrying current I are equally placed as shown in the figure Adjacent wires have current in opposite direction Net magnetic field at point `P` is
.
A. `(mu_(0)I)/(4pi)(In2)/(sqrt3a)hatk`
B. `(mu_(0)I)/(4pi)(In4)/(sqrt3a)hatk`
C. `(mu_(0)I)/(4pi)(In4)/(sqrt3a)(-hatk)`
D. zero