Which of the Following Variables Has Been of Assistance in Forecasting

Which of the following variables has been of assistance in forecasting the number of named tropical storms in the North Atlantic region?

A) When the western Sahel region of Africa is wet with an abnormally large number of thunderstorms
B) Abnormally warm sea-surface temperatures west of the Sahel region of Africa
C) The presence of an El Nino which tends to disrupt and break apart tropical cyclone
D) Low atmospheric pressure in the Caribbean region
E) All of these are correct