¿Qué es lo que te gusta hacer en el verano? (ir al campo)
What’s the answer?
ANSWER: Lo que me gusta hacer en el verano es ir al campo.
The answer you mentioned, that the system says is wrong, that one is talking about a balcony and a couch, the question you asked was talking about summer and going to the countryside, I was a little confused why everyone would say that but I hope that my answer helps! :)