Final answer:
The best response to the scenario is to directly approach Tiana, offer support, and walk with her, which is a form of direct intervention against the bystander effect and harassment.
Step-by-step explanation:
The scenario you're describing involves witnessing a form of harassment and considering how to respond to help your friend Tiana. This situation touches on the concept of the bystander effect, which indicates that people are less likely to intervene in a situation where others are present to witness the event. However, knowing Tiana personally may prompt you to act contrary to the bystander effect, making you more likely to help. The best course of action would likely be choice c: to approach Tiana and walk with her, engaging in conversation and ensuring her safety. This direct intervention not only provides immediate support but also offers a subtle sign to the group that their behavior is being monitored and is not acceptable. Furthermore, it's important to reflect upon and challenge societal responses to gender-based violence and work towards creating a community that does not tolerate such harassment.