A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic. It talks about what happens during the wet season. It sets the stage for the rest of the text. It does not use any words that need prior context. Why other lines are not chosen? Paragraph 2 starts with "Large" which makes it specific and not independent. Paragraph 3 starts with "The seeds" which uses the definite article and assumes prior knowledge. Paragraph 4 starts with "This natural process" which refers back to something not yet mentioned. Paragraph 5 starts with "Many tropical plant species" which is specific and not general.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it summarizes the main idea. It shows the importance of the process described in the earlier paragraphs. It wraps up the topic clearly.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): This pair connects because the first paragraph introduces the fruits that fall into the water. The second paragraph explains what happens to those fruits. This shows a logical order of events.
• Pair 2 (Paragraph 2 → Paragraph 3): This pair connects because the second paragraph talks about fish eating the fruits. The third paragraph explains what happens to the seeds after the fish eat the fruits. This shows a cause and effect relationship.
• Pair 3 (Paragraph 3 → Paragraph 4): This pair connects because the third paragraph describes how seeds are spread by fish. The fourth paragraph explains the result of this process, showing a logical order.
• Pair 4 (Paragraph 4 → Paragraph 5): This pair connects because the fourth paragraph explains how fish help spread seeds. The fifth paragraph shows why this is important for tropical plants. This shows a broader to specific strategy.