Highest B.M.R. occurs in

Options

A. Elephant
B. Rabbit
C. Human
D. Whale

Answer

To determine where the highest Basal Metabolic Rate (BMR) occurs, we need to understand a few key concepts related to BMR and its influencing factors.

### Step-by-Step Solution:

1. **Understanding BMR**:
- BMR stands for Basal Metabolic Rate, which is the rate of energy expenditure per unit time by endothermic animals at rest. It measures the energy required to maintain basic physiological functions.

2. **Factors Affecting BMR**:
- BMR is influenced by several factors, including body size, age, gender, and species. Generally, smaller animals tend to have a higher BMR compared to larger animals.

3. **Comparison of Animals**:
- When comparing different animals, it is important to note that BMR is inversely proportional to body size. This means that as the size of the animal increases, the BMR decreases.

4. **Identifying the Animal with the Highest BMR**:
- Among various animals, smaller mammals like rabbits typically have a higher BMR compared to larger mammals. This is due to their higher surface area-to-volume ratio, which leads to greater heat loss and thus a need for higher energy expenditure to maintain body temperature.

5. **Conclusion**:
- Based on the understanding that smaller animals have higher BMRs, we conclude that the highest BMR occurs in the rabbit.

### Final Answer:
The highest B.M.R. occurs in the rabbit.

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