A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of immigration policy in 2005. It gives a broad overview of the situation without needing prior context. It does not use any pronouns or definite articles that refer to previous ideas. Why other lines are not chosen? Paragraph 2 starts with 'Their', which is a pronoun that refers back to something not mentioned yet, so it is not independent. Paragraph 3 starts with 'At present', which needs context to understand. Paragraph 4 starts with 'However', which is a conjunction and shows a continuation of thought. Paragraph 5 starts with 'A lopsided', which uses 'A' but does not introduce a new topic clearly.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it concludes the discussion on immigration reform. It summarizes the main point that without a balanced approach, the efforts will not succeed. It wraps up the ideas presented in the previous paragraphs.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it continues the discussion about immigration policy. It shows what efforts are being made after the attention received in 2005. This is a logical order because it goes from a general statement to specific actions.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it explains what is happening with the efforts mentioned. It shows the logical order of events, moving from the actions being taken to their current status in the legislative process.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it discusses the need for comprehensive reform after mentioning the proposals. The use of 'However' shows a contrast, indicating that despite the proposals, more is needed for success.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 follows Paragraph 4 because it explains the consequences of not having a comprehensive approach. It shows a cause and effect relationship, where failing to consider all aspects leads to failure.