Can I ask for the best answers for the following questions of this problem? This is from my Law on Agency.

Problem #2

Ms Babe entered into a contract of sale for her toothbrush with Mr. Muscle stipulating that it would be payable in 10 monthly installments at Php 1,000 for each installment payable at the first day of every month starting this day. The toothbrush is delivered at the moment of perfection of contract

1.) In case Mr. Muscle failed to pay the 2nd installment, as a general rule, Ms. Babe has the option to:

a. exact fulfillment of the obligation

b. cancel the sale

c. foreclose the chattel mortgage

d. all of the above

2.) In case Mr. Muscle failed to pay the 2 installments, as a general rule, Ms. Babe may:

a. exact fulfillment of the obligation only

b. cancel the sale or exact fulfillment of the obligation

c. foreclose the chattel mortgage only

d. none of the above

3.) In this case Mr. Muscle failed to pay the 2nd installment:

a. Ms Babe may foreclose the mortgage by procuring the possession of the toothbrush as payment of the debt

b. Ms. Babe may foreclose the mortgage and sell at public auction wherein the yield will be used for the payment of the price

c. Ms. Babe may foreclose the mortgage and sell at public auction wherein the yield will be used for the payment of the price however she cannot recover the unpaid balance from Mr. Muscle

d. Ms. Babe may not foreclose because there is no stipulation as to mortgage or foreclosure

4.) In this case Mr. Muscle failed to pay the 2 installments Ms Babe may:

a. exact fulfillment of the obligation only

b. cancel the sale then exact fulfillment of the obligation if cancellation is not possible

c. cancel the sale and exact fulfillment of the obligation

d. cancel the sale only

5.) In case Mr. Muscle failed to pay the 9th and the 10th installment, and it is stipulated that Ms. Babe may keep the installment payment:

a. Ms. Babe may keep the installment payment in all cases

b. Ms. Babe may keep the installment payment only if it is not unconscionable as determined

c. Ms. Babe may keep the installment payment only if it is unconscionable

d. The stipulation of keeping the installment payment is void