A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first line because it introduces Simard and gives important background information. It does not need any other sentence to understand it. It is a general statement about her birth. Why other lines are not chosen? Paragraph 2 starts with 'Her family' which uses a pronoun and needs context. Paragraph 3 starts with 'In her first stab' which is not general and needs more context. Paragraph 4 starts with 'Her job' which also uses a pronoun. Paragraph 5 starts with 'The fledgling plants' which uses 'the' and assumes prior knowledge.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the information about Simard's findings. It summarizes the problems she discovered with the plants, which is a good conclusion to her story.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the story of Simard's background. It shows her family and their work in logging, which relates to her early life.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it shows the next step in Simard's life. After her family work, she tries a career in logging, which is a logical order of events.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it explains what Simard did in her job. It shows her role in checking seedlings, which is related to her career in logging.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects with Paragraph 4 because it explains the results of Simard's job. It shows the problems with the seedlings she checked, which is a logical continuation of her work.