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 the Hundred Years' War. It gives a broad overview of the war and does not need any other sentence for context. It uses the definite article "the" to introduce a specific subject, which is acceptable here because it is the first mention of the war. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with "It" which is a pronoun and needs context. Paragraph 3 starts with "Throughout" which is a transitional word. Paragraph 4 starts with "Ultimately" which also indicates a continuation of thought.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the main ideas of the text. It uses the word "Ultimately" which signals the conclusion of the discussion about the war. It summarizes the outcome and reflects the overall theme of the text.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives more details about the war. The phrase "It began" refers back to the war mentioned in Paragraph 1. This shows a logical order where the first paragraph introduces the war and the second explains how it started.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it describes what happened during the war. The phrase "Throughout the war" shows that it continues the story from Paragraph 2. This is a logical order where the second paragraph explains the start and the third talks about the events during the war.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about the end of the war after discussing the events during it. The word "Ultimately" shows that it is the conclusion of the events mentioned in Paragraph 3. This is a logical order where the third paragraph describes the war's events and the fourth gives the outcome.