What best describes a confident demeanor that might also appear indifferent?

A confident demeanor that appears indifferent is best captured by the term "nonchalant." This word describes a relaxed or casual attitude where a person seems unconcerned or unfazed by circumstances that might typically elicit worry or emotion. The nonchalant individual presents an air of self-assurance but does so in a manner that gives the impression of emotional distance or indifference.

For instance, someone who approaches a stressful situation with calmness and a lack of visible concern would exemplify a nonchalant demeanor. This can sometimes be interpreted as confidence because the individual appears unruffled by obstacles or challenges. The essence of nonchalance is in its combination of self-possession and an understated or detached approach to interactions or situations, which aligns perfectly with the description given in the question.

Other choices do not encapsulate this blend of confidence and apparent indifference. "Omniscient" refers to having complete or unlimited knowledge, which does not relate to demeanor. "Malevolent" indicates a wish to do evil to others, which contradicts the notion of a confident yet indifferent attitude. "Scrupulous" describes someone who is diligent and extremely attentive to detail, which again does not fit the concept of a relaxed or indifferent demeanor.