6455. Ashish did not admit his mistake in the beginning.

✅ The correct answer is option C.
Commit : perpetrate or carry out (a mistake, crime, or immoral act).

Apologize : express regret for something that one has done wrong.

Accept : receive as adequate, valid, or suitable.

Realise : become fully aware of (something) as a fact; understand clearly.

Admit : accept as valid.

Synonym of Admit is Accept