The protective coloration by which frogs keep changing colors to hide from enemies is called 

Options

A. mimicry
B. camouflage
C. melanism
D. all the above

Answer

To answer the question about the protective coloration by which frogs keep changing colors to hide from enemies, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Options**: The options given are mimicry, camouflage, melanism, or all of the above. We need to analyze each term to determine which one accurately describes the color-changing ability of frogs.

2. **Defining Camouflage**: Camouflage refers to the ability of an organism to blend in with its surroundings by changing its color or pattern. While frogs can exhibit camouflage, it is not the primary term used for their color-changing behavior.

3. **Defining Mimicry**: Mimicry is when an organism evolves to resemble another organism or object, often for protection against predators. Frogs can exhibit mimicry by changing their colors to resemble their environment or other organisms, which helps them avoid detection by predators.

4. **Defining Melanism**: Melanism is a condition where an organism has an increased amount of dark pigmentation. This is not specifically related to the ability of frogs to change colors for hiding; rather, it is a different phenomenon.

5. **Conclusion**: Based on the definitions and understanding of the terms, the most appropriate answer to the question is "mimicry," as it specifically relates to the protective coloration that frogs use to hide from enemies.

### Final Answer:
The protective coloration by which frogs keep changing colors to hide from enemies is called **mimicry**.

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