Which Description Implies a Drop in Interest Rates

Which description implies a drop in interest rates?

A) either a leftward shift of the demand curve for loanable funds,or a rightward shift of the supply curve
B) either a leftward shift of the supply curve for loanable funds,or a rightward shift of the demand curve
C) a rightward shift of both the supply and the demand curves for loanable funds
D) a leftward shift of both the supply and the demand curves for loanable funds
E) simultaneous downward movement along fixed demand and supply curves for loanable funds