Which airspace is defined as a transition area when designated in conjunction with an airport which has a prescribed IAP?

The Class E airspace extending upward from 700 ft or more above the surface and terminating at the base of the overlying controlled airspace.

Explanation:

The Class E airspace extending upward from 700 ft or more above the surface and terminating at the base of the overlying controlled airspace is defined as transition area.

In Class E, Instrument Flight Rules aircraft are controlled by Air Traffic Controller.

In the vast majority of areas, there are enough airports and victor airways to have Class E begin at 1,200 feet above ground level (AGL). This is known as enroute Class E airspace.