The success of mammals on earth is largely because

Options

A. They can conform to the changes in the environment .
B. They can reduce metabolic activity and go into state of dormancy during unfavourable conditions in the environment
C. They have the ability to maintain consant body temperature
D. They can take care of their young ones as they have mammary glands to suckle them.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the reasons for the success of mammals on Earth. We need to analyze the provided options to determine which one best explains this success.

2. **Evaluating the Options**:
- **Option A**: "They can conform to the changes in the environment."
- This option refers to adaptation. While adaptation is important for survival, it is not unique to mammals. Therefore, this option is incorrect.

- **Option B**: "They can reduce metabolic activity and go into a state of dormancy during unfavorable conditions."
- This describes hibernation, which is a strategy used by various animals, not just mammals. Thus, this option is also incorrect.

- **Option C**: "They have the ability to maintain constant body temperature."
- This refers to homeostasis, specifically thermoregulation. Mammals are endothermic (warm-blooded), allowing them to maintain a stable internal temperature regardless of external conditions. This ability is crucial for their survival and adaptability, making this option correct.

- **Option D**: "They can take care of the young ones as they have mammary glands to nourish them."
- While parental care and the ability to nurse young are important, this trait alone does not account for the overall success of mammals in diverse environments. Thus, this option is incorrect.

3. **Conclusion**: After evaluating all options, the correct answer is that the success of mammals on Earth is largely due to their ability to maintain a constant body temperature (homeostasis).

### Final Answer:
The success of mammals on Earth is largely because they have the ability to maintain constant body temperature.

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