am i right?

Assume that Carol cleans Dawn's house weekly for $80. Dawn would be willing to pay as much as $100 weekly to have his house cleaned. Carol’s opportunity cost is $70.

If Carol cleans Dawn's house, the producer surplus is

1. $80.

2. $70.

3. $100.

4. $10.

5. None of the answers is correct.
Answer 5. Am i right? so confused