There are 4 processses A,B,C,D arrived in to the ready queue at time 0 in the order A,B,C,D. The burst time are 4,2,1,2 respectively. RR scheduling technique is used with time slice of 1ms. If the context switch takes 2ns then what will be the total time taken(ns) for all the context switches to finish the process execution?
a)12ns b)14ns c)16ns d)10ns