LOS ANGELES — The answer to the trivia question will be: ‘‘Monkey Drums (Goskel Vancin Remix), by Chase Buch.’’

That was the 25-billionth song purchased on iTunes.

Apple Inc. announced the sales milestone Wednesday. The company said Phillip Lupke of Germany purchased Buch’s song and will receive an iTunes gift card worth $13,500.

It took the Cupertino, ­Calif., company almost 10 years to reach the milestone. Customers download an average of 15,000 songs a minute from the iTunes Music Store, which was launched in April 2003. The catalog is 26 million songs deep.