Emma trusts her colleague Natalie, as she is very forthright and trustful. Emma can trust her to keep something in confidence. The factor responsible for Emma's trust in Natalie, in the given example, is

The correct answer is character

The fact that Emma is able to trust Natalie is because she is a person of character. This is an important aspect when it comes to trust.

Character is a set of characteristics and traits related to an individual or group's way of acting and reacting. It is a moral character. It is the firmness and consistency of attitudes. The set of qualities and defects of a person is what will determine his conduct and his morality, his character.