In 1997, There Was a Speculative Attack on the Thai

In 1997, there was a speculative attack on the Thai baht. This resulted from the:

A) belief by speculators that the Thai central bank had an oversupply of U.S. dollar reserves.
B) belief by speculators that the Thai central bank didn't have sufficient U.S. dollar reserves to maintain the current fixed rate.
C) revelation that the Thai central bank had converted its gold reserves into foreign exchange.
D) overthrow of the Thai president and the central bank.