Stratified drift consists mostly of

The correct answer is - sorted and stratified debris.

The stratified drift is a result of the glacial movement and melting (mostly during the summer months). It is consisted of sorted and stratified debris, in the form of finely grained rocks and sands that have been deposited in front of the glacier by the little streams of melting water from it. The stratified drift is often cut by little streams of the melting water from glaciers, when it is the warmest period of the year.