Polar bears are carnivores and prey on many arctic birds and fishes. However, under natural conditions, no one found polar bears predating any penguin. This is because [CDS]

• A. penguins have chemical substance in their muscles which is toxic to polar bears
• B. penguins are gregarious and always move in groups. Therefore, a polar bear cannot approach them
• C. polar bears and penguins never coexist under natural conditions. The former lives in the North Pole while the latter lives in the South Pole
• D. None of these