Final answer:
The component that helps maintain a relationship despite unpredictability in a partner's behavior is commitment, according to Sternberg's Triangular Theory of Love, making 'faith' the correct answer.
Step-by-step explanation:
According to Robert Sternberg's Triangular Theory of Love, the component that helps maintain a relationship despite unpredictability in a partner's behavior is commitment. Commitment is the decision to stay with another person and having the determination to work through difficulties. In Sternberg's theory, consummate love is described as having all three components of love: intimacy, passion, and commitment. This type of love represents a healthy and balanced relationship, where both partners are committed to each other, share a deep emotional connection (intimacy), and maintain physical attraction (passion). Based on this, the correct answer to the given question would be D. faith, demonstrating trust and belief in the partner and the relationship's stability over time, even when behavior may change.