A magnetic field of 2×10⁻² T acts at right angles to a coil of area 100 cm², with 50 turns. The average e.m.f. induced in the coil is 0.1 V, when it is removed from the field in t sec. The value of t is
A. 10s
B. 0.1 s
C. 0.01 s
D. 10 s