First sentence: Why this is the first line? This paragraph is the first line because it introduces the main topic of ocean pollution. It is a general statement that does not need other sentences for context. It sets the stage for the discussion about ocean pollution. Why other lines are not chosen? Paragraph 2 starts with 'This pollution', which refers back to ocean pollution, so it is not independent. Paragraph 3 starts with 'Efforts', which is not a general statement. Paragraph 4 uses 'This', which also refers back to previous information. Paragraph 5 starts with 'Millions', which is not a general statement.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the discussion by talking about solutions to ocean pollution. It gives a final thought on how to address the issue.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives a specific example of ocean pollution. This follows the Broader to Specific Strategy.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it explains what happens to marine life due to plastic waste. This follows the Cause and Effect Relationship.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about the broader impact of pollution on ecosystems. This follows the Logical Order.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects to Paragraph 4 because it discusses solutions to the pollution problem. This follows the Topic Example Strategy.