One of the most important problems we will have to solve is ____of students’ learning method.

One of the most important problems we will have to solve is ____of students’ learning method.

1. A.
   that
2. B.
   this
3. C.
   what
4. D.
   Which

One of the most important problems we will have to solve is _______ of students’ learning method.

A. that           B. this            C. what          D. which

One of the most important problems we will have to solve is ____of students’ learning method.

A. that           B. this            C. what          D. Which

One of the most important problems we will have to solve is _______ of students’ learning method．

A．that          B．this           C．what            D．which