Which of the following frequencies is audible to human beings ?

Options

A. 5 Hz
B. 27 Hz
C. 5 kHz
D. 50 kHz

Answer

To determine which of the given frequencies is audible to human beings, we need to understand the range of human hearing.

### Step-by-Step Solution:

1. **Understand the Audible Range**:
- The typical audible range for humans is from **20 Hz to 20 kHz** (20,000 Hz). Frequencies below 20 Hz are considered infrasonic, and those above 20 kHz are considered ultrasonic.

2. **Evaluate the Given Frequencies**:
- We need to check the provided options against the audible range:
- **Option A: 5 Hz** - This frequency is below 20 Hz, thus it is not audible to humans.
- **Option B: 27 Hz** - This frequency is above 20 Hz, thus it is audible to humans.
- **Option C: 5 kHz (5000 Hz)** - This frequency is well within the audible range, thus it is audible to humans.
- **Option D: 25 kHz (25000 Hz)** - This frequency is above 20 kHz, thus it is not audible to humans.

3. **Identify the Audible Frequencies**:
- From the evaluation:
- **Option B (27 Hz)** and **Option C (5 kHz)** are within the audible range.
- **Options A (5 Hz)** and **D (25 kHz)** are not audible.

4. **Conclusion**:
- The frequencies that are audible to human beings from the options provided are **Option B (27 Hz)** and **Option C (5 kHz)**.

### Final Answer:
The frequencies that are audible to human beings are **27 Hz and 5 kHz**.

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