Afold-thrust belt is a. a low-lying region where precambrian rocks crop out b. a low-lying region where precambrian rocks are covered by phanerozoic sedimentary strata c. a region of compressed rock located behind a volcanic arc at a convergent continental margin d. synonymous with ""craton""

The answer is C:

a region of compressed rock located behind a volcanic arc at a convergent continental margin.

explanation:

Typically found in orogenic forelands or in rear-arc position (e.g. on east side of Andes). It's formed during continent-continent collision, and often in passive margin sediments of the subducting plate (and hence can exhume the earlier rift margin that formed the foundation for the passive margin.