ANSWER: A. 25% academic scholarship, 50% Grants, 25% subsidized loans
EXPLANATION: The lowest cost to the student means the lowest expenditure of the student for his education.
Going by the option A if the student receives 25% academic scholarship, 50% grants and 25% subsidized loans, the student's expenditure will only be repaying the loan amount. Academic scholarships and Grants are non-repayable fund and are thus waived off from his educational expenditure.
If the student gets 50% academic scholarship and 50% subsidized loans, then he will have to pay back 50% of the academic fees compared to the option A where only 25% was needed to be repaid.
Similarly, for the next two options, the subsidized loan facility doesn't fall to 25%. So these options will be costing more to the student.