Question

I visited Brazil in April. I (stay) at a nice hotel for a fortnight. A stayed B had stayed C had been staying D was staying​

Answer 1

ответ - А I (stayed) at...

Answer 2

The correct answer would be D) was staying.

"I was staying at a nice hotel for a fortnight."

This choice uses the past continuous tense ("was staying") to describe an ongoing action that was happening in the past. Since you mentioned that you visited Brazil in April and stayed at a hotel for a fortnight (two weeks), the past continuous tense is the most appropriate choice.