When did Nadia’s friend arrive at the restaurant?

The answer indicating that Nadia's friend arrived at the restaurant "as she was leaving" suggests that the friend arrived at the moment Nadia was just about to exit. This type of timing highlights a significant coincidence where both events occur simultaneously, implying that Nadia's friend missed her by a narrow margin. This situation conveys a sense of timing and opportunity, often used in narratives to create dramatic or ironic moments.

In understanding the context of the other options, it's important to see how they differ. The option that suggests her friend arrived "as she was just arriving" implies they arrived at the same time, which would negate the dramatic implication of a missed connection. The choice indicating that her friend arrived "before she entered" suggests that the friend was already there when Nadia arrived, which does not capture the sense of timing. Lastly, saying her friend arrived "right after she sat down" again changes the time frame to a later point that doesn’t align with Nadia almost leaving, thus diminishing the tension of the scenario. Each option represents a different timing that shifts the nature of the interaction, but "as she was leaving" provides that poignant moment of missed opportunity.