From the given options, select the OPPOSITE in meaning to the given word:

"Conscientious"

Irresponsible

The correct answer is: Option (3) → Irresponsible

Conscientious means being careful, diligent, and responsible in doing one's work or duty. Irresponsible is the opposite, referring to someone who does not take responsibility or act with care.

Option (1) Mutual means shared between two or more parties – unrelated in meaning.

Option (2) Scrupulous means very careful and morally upright – a synonym, not an antonym.

Option (4) Meticulous means showing great attention to detail – also similar in meaning to conscientious.