The correct answer is D, approximately 2.14%.

First calculate commission on the initial $5,000,000:

$5,000,000 × 1% = $50,000.

The agent earned $125,000 in total, so commission attributable to sales above $5 million is:

$125,000 − $50,000 = $75,000.

Now calculate the sales volume above the threshold:

$8,500,000 − $5,000,000 = $3,500,000.

Determine the rate:

$75,000 ÷ $3,500,000 = 0.02142857

Converted to a percentage:

0.02142857 × 100 = approximately 2.14%.

Therefore D is correct.

This is a reverse commission calculation: instead of being given the rate and finding commission, the candidate derives the percentage from total compensation and sales volume.

The key is separating the two compensation tiers before dividing.

Study Guide Reference: Real Estate Calculations — commissions, percentages and tiered compensation calculations.