The terms in I are like terms. This is because both terms have the same variable x^{2}

Step 2

The terms in II are like terms. This is because these terms have the same variable x^{2} and y^{3} even though both variables are written in a different order.

Step 3

The terms in III are unlike terms. This is because these terms have variables with different exponent (i.e. power).

Step 4

The terms in IV are like terms. This is because both terms have the same variable m.

Step 5

The terms in I, II and IV are likes terms. Clearly, the answer is C.