A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of African tribal masks. It gives a broad overview of their importance in cultural heritage without needing prior 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 stand alone. For example, Paragraph 2 starts with 'Crafted,' which is not independent. Paragraph 3 starts with 'Moreover,' which is a conjunction. Paragraph 4 starts with 'Therefore,' which also shows it is not independent.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the main ideas about the masks. It summarizes their importance and gives a final thought on how they are viewed in culture. The word 'Therefore' signals that this is a conclusion.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives more details about the masks. It explains what the masks represent, which is a specific point following the general idea in Paragraph 1. This is a Broader to Specific Strategy.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it adds more information about the masks. It shows how the creation and use of masks are different in various cultures. The word 'Moreover' is a Connector that shows this relationship.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it explains the importance of the masks. It shows that because of their creation and use, they are celebrated. The word 'Therefore' is a Connector that shows this cause and effect relationship.