Which of the following place have subzero temperature :
(a) High altitude place
(b) Hydrothermal vent
(c) Polar area
(d) Tropical desert

Options

A. a & c
B. a, b & c
C. Only c
D. a, b, c & d

Answer

To determine which of the given places have sub-zero temperatures, we will analyze each option step by step.

### Step 1: Understand the Definition of Sub-Zero Temperature
Sub-zero temperature refers to any temperature that is below 0 degrees Celsius (or 32 degrees Fahrenheit).

### Step 2: Analyze Each Option
1. **High Altitude Place**:
- At high altitudes, the air pressure is lower, and temperatures tend to drop significantly. It is common for high-altitude regions, such as mountains, to experience sub-zero temperatures, especially during the night or in winter.
- **Conclusion**: This option can have sub-zero temperatures.

2. **Hydrothermal Vent**:
- Hydrothermal vents are found on the ocean floor and are known for their high temperatures due to geothermal activity. The water around these vents can reach temperatures of up to 400 degrees Celsius.
- **Conclusion**: This option does not have sub-zero temperatures.

3. **Polar Area**:
- Polar areas, such as the Arctic and Antarctic regions, are characterized by extremely cold climates. Temperatures in these regions are often well below freezing, making them sub-zero.
- **Conclusion**: This option definitely has sub-zero temperatures.

4. **Tropical Desert**:
- Tropical deserts, like the Sahara, experience very high temperatures, typically ranging from 29 to 35 degrees Celsius during the day. Even at night, while temperatures may drop, they do not usually reach sub-zero levels.
- **Conclusion**: This option does not have sub-zero temperatures.

### Step 3: Final Selection of Correct Options
Based on the analysis:
- **Correct Answers**: High altitude place and Polar area.
- **Incorrect Answers**: Hydrothermal vent and Tropical desert.

### Final Answer
The places that have sub-zero temperatures are:
- (a) High altitude place
- (c) Polar area