4 is CORRECT. (.375)10=(.011)2, by multiplying .375 by 2 three times and recording the carries: .375 by 2 = 0.750 with c = 0; .750 by 2 = 1.500 with c = 1; .500 by 2 = 1.000 with c = 1. Stop here because 000 was reached. Read the c numbers forwards to get .011