Transportation of 35% oleum during winter suffers from the problem of freezing, which can be overcome by the addition of small quantity of_____________________?

Transportation of 35% oleum during winter suffers from the problem of

1.	Transportation of 35% oleum during winter suffers from the problem of freezing, which can be overcome by the addition of small quantity of_____________________?
A.	Nitric acid
B.	Hydrochloric acid
C.	Methyl alcohol
D.	Formic acid
Answer» B. Hydrochloric acid