Answer:
The correct option is A: A baby boom begins, investor confidence rises.
Step-by-step explanation:
The main combination of factors that would cause equilibrium interest rate to fall and equilibrium quantity of loanable funds to rise is when there are many more individuals in their middle age than there are older people, and an increase in wealth. The presence of many middle aged individual would likely indicate the beginning of a baby boom and wealth increase in an economy shows confidence in investors.