Quiz: streams and pipelines

Read the output

Why does the address 203.0.113.7 appear on two lines?

$ cut -d' ' -f1 access.log | uniq -c | head -n 5
      1 192.0.2.201
      1 192.0.2.14
      1 203.0.113.7
      1 198.51.100.23
      3 203.0.113.7

• A uniq -c counts requests per minute.
• B The log has two different addresses that look the same.
• C uniq glues together repeats that stand in a row, and there is no sort before it.
• D head repeated a line when it cut the output short.