The noun form of approve is— (১৮তম শিক্ষক নিবন্ধন স্কুল: ২০২৪)

The correct answer is option (d) "approval." 'Approve' (verb) → 'Approval' (noun). The suffix '-al' is added to form the noun. Example: 'The project received approval from the board.' Other verb → noun with '-al': arrive → arrival, refuse → refusal, dismiss → dismissal, propose → proposal. ✗ 'Approof', 'approveness', 'approvally' are all incorrect forms. Source: English Vocabulary in Use — Cambridge.