A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of motivation. It is a general statement that does not need another sentence for context. It sets up the theme of the text without going into details. 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 is specific and refers back to motivation, so it cannot be first. Paragraph 4 talks about applying principles, which needs the context of motivation first.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the text. It shows the result of applying the principles discussed earlier. It concludes the ideas about motivation and its application.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it explains what drives motivation. This shows a logical order where the first paragraph introduces motivation, and the second explains its forces.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it gives examples of motivational theories. This shows a broader to specific strategy, where the second paragraph talks about forces, and the third gives specific theories.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about applying the theories. This shows a logical order where the third paragraph gives theories, and the fourth explains how to use them.