A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic about avocados. It gives a clear statement about what avocados are. This follows the rule of Topic Sentence. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'They', which is a pronoun. This means it needs more context. Paragraph 3 also starts with 'Avocados', but it is not a general statement. It talks about a specific use of avocados. Paragraph 4 starts with 'However', which is a conjunction and shows a contrast, so it cannot be the first sentence.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the discussion about avocados. It gives a final thought about how to eat them. This follows the rule of Conclusive Words, as it provides a conclusion about moderation.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the topic of avocados. It uses the Connector strategy. The first sentence introduces avocados, and the second sentence gives more information about their health benefits.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it adds more details about avocados. It uses the Broader to Specific Strategy. The second sentence talks about health, and the third sentence talks about how avocados can be used in cooking.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it gives a warning about eating avocados. It uses the Cause and Effect Relationship. The third sentence talks about how to use avocados, and the fourth sentence explains why moderation is important.