Its a period of 4 years for which the loan has been taken.
The loan amount is $27,800.00.
The outstanding amount at the and of three years, which is 36 months is shown as $7972.92 ( The Right Corner below)
Hence the Principal amount paid after a period of three years
= 27,800.00 - 7972.92
=$19,827.08
Hence the total amount repaid as principal at the end of three years is $19,827.08.
Option c) is the right answer