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 who cannot supply certain substances. It does not need another sentence for context. It does not start with a conjunction or use pronouns. Why other lines are not chosen? Paragraph 2 starts with 'Unless' which is a conjunction, so it cannot be independent. Paragraph 3 uses 'Unless' too, so it is not independent. Paragraph 4 starts with 'Additionally', which is also a conjunction, so it cannot be independent.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it gives the final consequence of breaking the rules. It wraps up the main ideas by showing what happens if the rules are not followed.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it explains more about who cannot supply substances. It uses 'Unless' to show a condition. This is a Connector strategy.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it adds more information about wholesalers. The word 'Additionally' shows that it is giving more details. This is a Broader to Specific strategy.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about the consequences of not following the rules. It shows a cause and effect relationship.