Penguins are flightless but fast swimmers.

Penguins are flightless but fast swimmers.

• A. They Fly Well Underwater
• B. Flightless Birds That Are Fast and Graceful Swimmers
• C. They Cannot Swim
• D. They Migrate Across Continents

Answer: (B)

Penguins show a clear link between anatomy and lifestyle: they are birds that have lost air-flight but gained exceptional underwater propulsion. Their wings are shaped into powerful flippers, their bodies are streamlined, and their muscles are built for strong, rapid strokes through water. Because of this, they move through the ocean with speed and grace, making them among the fastest swimmers among birds. The description that fits best is that they are flightless birds that are fast and graceful swimmers, capturing both their inability to fly and their impressive aquatic mobility. The idea of flying underwater isn’t accurate for penguins, they clearly swim rather than cannot swim, and they don’t routinely migrate across continents on land, so those statements don’t describe them accurately.