54 If a CA in practice or a firm of CA has more than one office in India, each one of such offices should be in the separate charge of a person. However, exemption from separate incharge is available in case of second office if it situated: (a) in the same premises where partner’s office is situated, (b) in the same city, (c) within 50 kms. from the first office. (d) either (a) or (b)
 
Answer by Author is “C” but i would say all of the above should be the answer, seems to be typo error

Sir it should be (d)… bcoz option c say 50km from office instead from municipal limit?

if it is within 50km of office it is definitely within 50km of municipal limits