Which of the following is a common plant-based example of a behavioral adaptation?

• A. Bending toward sunlight (tropism)
• B. Growing thorns
• C. Developing a waxy cuticle
• D. Producing seeds

Answer: (A)

Plants respond to their environment with growth and physiological changes, which can count as behaviors. Bending toward a light source is a classic example of a behavioral adaptation called phototropism. When light comes from one side, the plant distributes more of the growth hormone auxin on the shaded side. That causes cells on that side to elongate, so the stem or shoot curves toward the light. This growth response helps the plant maximize light capture for photosynthesis, tying the behavior directly to a survival advantage.

Other options illustrate different kinds of adaptations. Growing thorns is a structural feature that helps defend the plant, not a response to light or other stimuli. Developing a waxy cuticle is a protective surface adaptation that reduces water loss. Producing seeds is part of reproduction, not an immediate behavioral response to the environment.