A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first line because it introduces the main idea of the event planning. It sets the stage for what will happen next. It does not refer to anything before it, so it is independent. This follows the rule of Topic Sentence. Why other lines are not chosen? The other paragraphs are not chosen because they do not meet the criteria for being independent. For example: - Paragraph 2 starts with 'In preparation,' which connects to the previous idea. - Paragraph 3 starts with 'As the guests began to arrive,' which also connects to earlier ideas. - Paragraph 4 starts with 'The final touch,' which assumes prior knowledge. - Paragraph 5 starts with 'Later that evening,' which indicates a time reference that needs context.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the event. It shows the result of all the planning and preparation. The phrase 'highlighting the success' indicates a conclusion to the story.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it continues the idea of planning the event. The phrase 'In preparation' shows a logical order of steps in the planning process.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it shows what happens after the invitations are sent. The phrase 'As the guests began to arrive' indicates a chronological order of events.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it describes the final details of the event. The phrase 'The final touch' shows a logical order of events leading to the cake reveal.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects to Paragraph 4 because it describes the outcome of the event. The phrase 'Later that evening' shows a chronological order, leading to the surprise moment.