It is high time he (change) his behaviour.

অপশনসমূহ
সঠিক উত্তর চিহ্নিত
ক change
খ has changed
গ changed
ঘ did change
ব্যাখ্যা ও সমাধান
After 'It is high time' followed by a subject, the past subjunctive/simple past form of the verb is used.