In which situation is it NOT possible to achieve a pressure compensation between the middle ear and the environment?

Question

Question PPL(A) - Private Pilot License - Human factor and limitations

QuizVDS · Accepted Answer

The eustachien tube is blocked

QuizVDS · Answer

During a light and slow climb

QuizVDS · Answer

All windows are completely closed

QuizVDS · Answer

Breathing takes place using the mouth only

Id 27 - PPL(A) EN - In which situation is it NOT possible to achieve a pressure compensation between the middle ear and the environment?