Where are subduction zones likely to form?

a. between two diverging continental plates
b. between converging oceanic and continental plates
c. between diverging oceanic and continental plates
d. between two diverging oceanic plates

B. Between converging oceanic and continental plates

Explanation:

Subduction happens when a tectonic plate slides under another one.

For this to occur, the two plates have to be converging towards each other.  

The plates running towards each other are usually an oceanic plate converging towards a continental plate, since continental plates are too far apart and separated by oceanic plates.  It could happen between two oceanic plates... but that's really an exception.

Diverging plates are not causing any subduction since they are running away from each other.  Just by that fact, you can eliminate the answers A, C and D.