Final answer:
Kaleigh should choose statement A: Having an online assignment portal will make life easier for teachers and students.
Step-by-step explanation:
To build trust with her audience, Kaleigh should choose statement A: Having an online assignment portal will make life easier for teachers and students. This statement focuses on the benefits of an online assignment portal, which aligns with Kaleigh's position that it would help reduce paper waste. By emphasizing the positive impact on both teachers and students, Kaleigh can gain the trust and support of her audience.