Select the option that can be used as a one-word substitute for the given group of words.
One who demands strict conformity to rules

Correct option is A

The correct one-word for the given group of words is Martinet.
A martinet is a person who demands complete obedience to rules and discipline, often being very strict and rigid in enforcing them. (Hindi meaning – सख्त अनुशासनप्रिय व्यक्ति)
Example: The headmaster was a martinet who tolerated no misbehavior.
Meanings of the given other options:
· Opthalmologist: A doctor who specializes in eye and vision care. (नेत्र चिकित्सक)
· Endodontist: A dentist specializing in diseases of the dental pulp and nerves of the teeth. (दंत नसों का चिकित्सक)
· Omnipotent: Having unlimited power or authority. (सर्वशक्तिमान)