Hello there, marie!
You've requested to change the security questions for your Mojang account. To proceed, please click the following link:
https://account.mojang.com/me/settings/changeSecretQuestions/b9426119845fc97567f4f6c83074d7013e095431
If you haven't requested to change your security questions, someone else may have logged into your account without your permission. If you suspect this might have happened, please change your password to make sure your account is as secure as possible.
Have a nice day,
Mojang.