Final answer:
During early adolescence, girls typically have greater intimacy in their friendships and tend to trust their friends more than boys, which corresponds with answer option d: both a and c only.
Step-by-step explanation:
With respect to gender differences in friendships during early adolescence, it's generally true that girls have greater intimacy in friendships than boys, and girls tend to trust their friends more than boys. Therefore, the correct answer is both a and c, which translates to option d: both a and c only.
Studies have shown that during this stage, girls often develop deeper emotional connections with their friends and confide in them more readily than boys do. Conversely, boys are socialized to engage in more activity-oriented friendships with less emotional disclosure, influenced by societal expectations of masculinity.