I have been studying the present perfect simple and the present perfect continuous tenses this week, and I have tried many exercises to improve my grammar. Then I tried this exercise, but I can't find the correct answer to the first question.
I thought the correct answer for the first question was:
you have been keeping a pet for 3 years.
But according to the website, the correct answer is:
You've kept a pet for three years.
Please explain when to use the present perfect simple instead of the present perfect continuous.