Metabolic rate is lowest in frog when it is

Options

A. Floating upon water surface
B. Sleeping underground
C. Quietly waiting for a prey
D. Resting upon ground

Answer

### Step-by-Step Solution:

1. **Understanding Metabolic Rate**: The metabolic rate refers to the rate at which an organism converts food into energy. It can vary significantly depending on the activity level and environmental conditions.

2. **Identifying Hibernation**: Frogs, like many amphibians, enter a state known as hibernation during adverse conditions, particularly in winter. This state is characterized by significantly reduced metabolic activity.

3. **Conditions During Hibernation**: During hibernation, frogs experience a drop in body temperature, often close to 0 degrees Celsius. Their respiration rate decreases to only a few breaths per minute, and their heartbeat becomes very slow.

4. **Behavior of Frogs During Hibernation**: Terrestrial frogs typically burrow into the ground to escape the cold, while aquatic frogs may remain at the bottom of ponds or lakes.

5. **Analyzing the Options**:
- **Floating upon water surface**: This is incorrect as frogs do not hibernate in this manner.
- **Sleeping underground**: This is correct as many frogs burrow underground during hibernation.
- **Quietly waiting for prey**: This is incorrect; during hibernation, frogs are not actively hunting.
- **Resting upon ground**: This is also incorrect as frogs are not simply resting; they are in a state of hibernation.

6. **Conclusion**: Based on the analysis, the metabolic rate is lowest in frogs when they are **sleeping underground** during hibernation.