Final answer:
The internal similarity between a lily and an apple is that both produce seeds inside a fruit, as they are angiosperms. This process of fruit production is a fundamental similarity despite any external differences.
Step-by-step explanation:
The internal similarities between a lily and an apple are found in their reproductive structures and processes. The correct answer to the question “What are the internal similarities between a lily and an apple?” is B. Both produce seeds inside a fruit.
Both a lily and an apple are angiosperms, which means they have flowers that develop into fruits. These fruits contain the seeds necessary for the reproduction of the plant. While there are differences, such as in the scent, color, and structure of their flowers, the fundamental process of producing seeds within a fruit is a similarity they share.
Option C, stating that both undergo photosynthesis, is correct but does not specifically address the internal similarities inquired about by the question.