A mortgage that covers several parcels of land and contains a provision that allows for the sale of an individual parcel with clear title is called:

Answer: Blanket mortgage

Explanation:

A blanket mortgage is defined as mortgage which is funded for buying multiple real estate property area. This is also known as blanket loan. In this scenario, a developer can use blanket mortgage instead of using single mortgage for sub-divided property

These loans are usually taken by developers and builders for a particular real estates property which is divided into pieces for selling them individually one by one or any certain time.