Can you please help me with the following question?

The liquidity preference theory is most accurately stated as:

a.The forward rate is an unbiased predictor of future spot rates

b.Premiums exist to compensate investors for added interest rate risk accepted when lending long term

c.Lender and borrower preferences determine the shape of the yield curve

d.Investors have preferences that are associated with particular maturities for various reasons (risk, cash flow matching, etc.)