In the following sentence, four words printed in bold type are given. One of these words printed in bold might either be wrongly spelt or inappropriate in the context of the sentence. Find out the word that is inappropriate or wrongly spelt, if any. If the words printed in bold are correctly spelt and appropriate in the context of the sentence then mark 'No error’ as your answer.

He was unable to ace the exam and was really depressed. His best friend was trying to bemuse him by making weird faces.