Read the excerpt from the story Animals in the Zoo:

(17) It was time for Rueben's mom to examine the tamarins, so they headed to the Primate Discovery Center. They walked into the veterinarian's room so that his mother could examine the tamarins. The public wasn't allowed to see them until Rueben's mother had looked them over and made sure they were healthy. The room was white, very sterile, and looked like an operating room that you would see on TV. Rueben's eyes widened and a look of uneasiness crossed his face. He was scared, and his mother noticed right away.

(18) "Don't worry, we won't be operating on the tamarins today. We are just checking their health and looking at their eyes, ears, and hands during this visit. We want to make sure they are healthy enough to be put into their enclosure," she said. Just then, a zoo employee brought in the two tamarins, and Rueben immediately understood why they were called cotton-top tamarins. Each of them had a white tuft of hair on top of their head. The zoo employee told Rueben and his mom that these two tamarins were the first of many to come to the zoo. If these two stayed healthy and appeared to be happy in their enclosure, the zoo would be able to get even more tamarins to fill the exhibit which is why they wanted to make sure they had an expert come in to examine them.

How do the events in paragraphs 17 and 18 contribute to the reader's understanding of Mom's feelings toward Rueben?

A: By entering into the vet's room, his mom shows that she doesn't care about Rueben's feelings.

B: By entering into the vet's room, his mom shows that she is really excited to see the tamarins.

C: By telling him not to worry, his mom shows that she is embarrassed by Reuben's fear.

D: By telling him not to worry, his mom shows that she wants to reassure Reuben and calm him.

To determine how the events in paragraphs 17 and 18 contribute to the reader's understanding of Mom's feelings toward Rueben, we can closely examine the details provided in the excerpt.

In paragraph 17, Rueben's mom brings him to the Primate Discovery Center to examine the tamarins. This shows that she involves Rueben in her work and values his presence enough to take him along. Additionally, Rueben's fear is immediately noticed by his mother. This suggests that she is attentive to his emotions and takes his feelings into consideration.

In paragraph 18, Rueben's mom reassures him by saying, "Don't worry, we won't be operating on the tamarins today." This indicates that she knows Rueben is scared and wants to alleviate his fears by addressing his concerns directly. She also explains the purpose of the visit and emphasizes that they are checking the tamarins' health, not performing any invasive procedures. This demonstrates that she wants to reassure Rueben and calm him, showing her concern for his well-being.

Based on this analysis, the correct answer is D: By telling him not to worry, his mom shows that she wants to reassure Rueben and calm him.