Final answer:
The cost of the loan will be PKR 0.
Step-by-step explanation:
To calculate the cost of the loan, we need to find the total amount repaid over the 4-year period.
The loan is repayable in four equal annual installments, so each installment will be PKR 15,000 / 4 = PKR 3,750.
Now, let's calculate the total amount repaid over 4 years: PKR 3,750 x 4 = PKR 15,000.
Therefore, the cost of the loan will be the total amount repaid minus the initial loan amount: PKR 15,000 - PKR 15,000 = PKR 0. So, the correct answer is a) PKR 15,000.