The Younger Dryas Refers to A(n)

The Younger Dryas refers to a(n)

A) interglacial period,characterized by a general warming trend,lasting since the last glacial maximum (LGM) to the present.
B) 400 year,from A.D.800 to 1200,period characterized by warmer than normal conditions in the North Atlantic region (e.g.Greenland and Iceland) .
C) brief return to near-glacial conditions during the transition period from the last glacial period to the present interglacial period.
D) global cooling episode,lasting from approximately A.D.1250 to 1850.