Which of the following statements is CORRECT?

a. A bond is likely to be called if its coupon rate is below its YTM.

b. A bond is likely to be called if its market price is below its par value.

c. Even if a bond’s YTC exceeds its YTM, an investor with an investment horizon longer than the bond’s maturity would be worse off if the bond were called.

d. A bond is likely to be called if its market price is equal to its par value.

e. A bond is likely to be called if it sells at a discount below par.

Please, explain why? I asked this question a number of times and every time the answer given was different...Please, help and be accurate.