Statement:
I am surprised to find that every student is studying only English but not his or her mother tongue.
Assumptions:
I. It is a good sign that everybody is studying only English.
II. It is a bad sign that nobody is studying his or her mother tongue.
Answer: C
The opinion of the author must be either favourable [as given in (I)] or against [as given in (II)] to the phenomenon explained in the statement. Hence, either (I) or (II) is an assumption.