In Volatile Markets,"speculators" Would Be Expected to Provide Some Stability

In volatile markets,"speculators" would be expected to provide some stability because:

A) they will be required to do so by the government.
B) they will use current price moves to predict future moves.
C) they will buy when price is below equilibrium and sell when it is above equilibrium.
D) they will buy when price is above equilibrium and sell when it is below equilibrium.