This can be a matter of cultural custom, and so it is important to know to whom you are speaking, and remember the customs of the culture one is in. In Japanese culture and in some others, it is grossly impolite/disrespectful and considered even confrontational to make direct eye contact in conversation.
In the US, it is typically assumed that direct eye contact is a sign of both attentiveness and respect (and even honesty) when answering a question.
In the US, it is typically assumed that direct eye contact is a sign of both attentiveness and respect (and even honesty) when answering a question.