Which of the following best illustrates a trade-off in natural selection?

• A. Birds with larger beaks can crack hard seeds but struggle to eat small seeds efficiently.
• B. A plant evolves thorns to protect against herbivores with no other effects.
• C. Mammals develop thicker fur for warmth but still maintain the same agility.
• D. Fish that swim faster are more likely to escape predators without any downside.

Answer: (A)