Language-teaching app Duolingo has been accused of letting gender ideology “infect” its language classes after criticising JK Rowling in a German lesson.

In a session for intermediate-level students, users had to select the correct response – written in German – to the question: “Do you like books with Harry Potter as a character?”

The correct response was: “Yes, but in my opinion the author is mean.”

The wrong alternative answer said: “Yes, you’re right. I’m interested in sports.”

A spokesman for the app later said: “We apologise for any offence caused and will remove this content from the app.”