Camouflage

The correct answer is option 'B', camouflage.

Explanation:

Definition of camouflage:
Camouflage is a natural adaptation that allows an organism to blend in with its surroundings, making it difficult for predators or prey to spot them. This adaptation helps the organism to stay safe and increases its chances of survival.

Chameleon's color-changing ability:
A chameleon is a type of reptile that is famous for its ability to change its skin color. It has specialized cells called chromatophores in its skin that contain pigments. These pigments can expand or contract, allowing the chameleon to change the color of its skin.

Reasons for color change:
A chameleon changes its color primarily for two reasons:

1. Camouflage: One of the main reasons a chameleon changes its color is to blend in with its surroundings. The chameleon can match its skin color to the colors of the objects or environment it is in. This helps it remain hidden from predators, such as birds or snakes, and also allows it to approach prey, such as insects, without being noticed.

2. Communication: Chameleons can also change their color as a form of communication. They can display bright and bold colors to signal aggression or territoriality to other chameleons. They can also change their color to attract a mate or to show submission.

Adaptive advantage:
The ability to change color provides the chameleon with a significant adaptive advantage. It allows them to avoid being detected by predators and increases their chances of successfully capturing prey. This camouflage adaptation helps the chameleon to survive in its natural habitat.

In conclusion, the color-changing ability of a chameleon is an example of camouflage, as it allows the chameleon to blend in with its surroundings and remain hidden from predators or unnoticed by prey.