The amount of interest expense for the year ended December 31,2019 is:

A) $6,000.
B) $4,500.
C) $4,000.
D) $1,500.

The note payable is for $50,000 at 12% interest for one year, which means the total interest expense for the year is $6,000 ($50,000 x 0.12).

However, the interest expense for the year ended December 31, 2019, is only for 9 months (April 1, 2019 - December 31, 2019).

To calculate the interest expense for these 9 months, we need to multiply the principal amount of the note ($50,000) by the interest rate (12%) and then by the portion of the year during which interest has accrued (9/12, or 0.75).

$50,000 x 0.12 x 0.75 = $4,500

Therefore, the amount of interest expense for the year ended December 31, 2019, is $4,500.