Answer :
pqr = 1
so p,r must not be 0
so in rst = 0
r can't be zero so st = 0 so s= 0 and we see it also satisfies spr = 0
SO D) S
so p,r must not be 0
so in rst = 0
r can't be zero so st = 0 so s= 0 and we see it also satisfies spr = 0
SO D) S