What task did Marta ask Nick to do that he was reluctant about?

Marta asked Nick to put sunblock on her face and ears, which is often a task that can make someone feel uncomfortable or reluctant, especially if they are not familiar with the other person's boundaries or personal space. This task requires a certain level of intimacy and trust, as it involves applying a product directly onto someone else's skin. Nick's reluctance could stem from concerns about appropriateness, social norms, or personal comfort in performing a task that involves close physical contact.

In contrast, carrying a backpack, helping to climb a tree, or taking a picture of someone typically do not evoke similar feelings of discomfort or intimacy. These tasks are more straightforward and generally perceived as less personal, making them less likely to cause reluctance.