d>b>a>c
a>b>c>d
b>a>c>d
b>a>d>c
Correct option is C. b>a>c>d
Solution:- (C)b>a>c>d
−OCH3 and −CH3 is an activating group because of their +R and +I effect which favours electrophilic substitution on benzene ring and −Cl and −CHO are deactivating due to their −I and −M effect. Hence the order of electrophilic substitution reaction are-b>a>c>d