A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of the text, which is grapes and their nutritional value. It is a general statement that does not need any other sentence for context. It does not use any pronouns or definite articles that refer to previous information. Why other lines are not chosen? The other paragraphs are not chosen because they do not meet the criteria for being independent. For example, Paragraph 2 starts with 'In particular,' which is a transitional phrase. Paragraph 3 uses 'They' which is a pronoun that refers back to grapes, and Paragraph 4 starts with 'Grapes are also,' which connects back to the previous sentence.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it provides a specific detail that wraps up the discussion about grapes and their health benefits. It does not introduce new ideas but rather concludes the information about the types of grapes that are high in antioxidants.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it provides specific information about grapes. This follows the Broader to Specific Strategy, where the first sentence gives a general idea and the second sentence gives more details.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it continues to talk about the benefits of grapes. This follows the Logical Order rule, as it builds on the information about vitamin C and introduces more about antioxidants.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it gives a specific example of grapes that are high in antioxidants. This follows the Broader to Specific Strategy, where the third paragraph talks about antioxidants in general and the fourth paragraph specifies darker grapes.