Careful in performing duties

A. Punctual

B. Punctilious

C. Sincere

D. Pugnacious

Answer: Option B

Solution(By Examveda Team)

One word substitute is Punctilious.

Punctual: happening or doing something at the agreed or proper time.
Punctilious: showing great attention to detail or correct behaviour.
Sincere: free from pretence or deceit; proceeding from genuine feelings.
Pugnacious: eager or quick to argue, quarrel, or fight.