Only an inquisitive person can gain proper knowledge.

Answer: Option D

Inquisitive : having or showing an interest in learning things; curious.
Careless : not giving sufficient attention or thought to avoiding harm or errors.
Indolent : wanting to avoid activity or exertion; lazy.
Dull : lacking interest or excitement.
Uninterested : not interested in or concerned about something or someone.

Antonym of Inquisitive is Uninterested