Both of the tennis courts had nets replaced. which pronoun agrees with the underlined indefinite pronoun? ones his its their

Both of the tennis courts had *their* nets replaced.
The word "Both" indicates two nets replaced so it wouldn't be "ones" or "its" because those show a singular net when that's not the case.
"His" would indicate that the tennis court nets belonged to a male but nothing in the sentence shows that so "their" would be appropriate.