Read the two stories. Story 1:
Amelia could not find her dog, Rocky, so she started to look for clues. She searched the fence and discovered a large, muddy hole under one section. She crawled through the hole and walked toward the neighbor’s house. Muddy paw prints covered the porch steps. Amelia knocked on the back door and suddenly heard a bark. She had found her dog.

Story 2:
For the science fair, Peter was measuring how sunlight affected plants. Each day he watered his plants and tracked their progress. One day, he noticed that all the plants were starting to droop. Something was fishy, so Peter began to investigate. He discovered soapy water on the table. Soapy water is harmful to plants. He waited after school and hid behind a desk to see if someone was messing with his plants. Ten minutes later, he saw Emily enter the room, make a soapy mixture, and pour it into the plants. She was caught red-handed.

What sentence from the second story shows that the theme is similar to the theme of the first story?
A. “Each day he watered his plants and tracked their progress.”
B. “Something was fishy, so Peter began to investigate.”
C. “Soapy water is harmful to plants.”
D. “Ten minutes later, he saw Emily enter the room, make a soapy mixture, and pour it into the plants.”