A particle with charge −e has velocity v=2i^+3j^ms−1 when it enters a region having uniform magnetic field B=4k^T. Which one of the following vectors gives the correct direction of the magnetic force on the particle?
a) 12i^−8j^
b) −3i^+2j^
c) −12i^+8j^
d) −8i^+12j^