The measurement of small time intervals became possbile with the development of :

Options

A. sand clock
B. sundial
C. pendulum clock
D. water clock

Answer

**Step-by-Step Solution:**

1. **Understanding Time Measurement**: Time measurement has evolved over the years, and various devices have been used to measure time intervals.

2. **Types of Time Measurement Devices**: The question lists four devices: sand clock, sundial, pendulum clock, and water clock. Each of these devices has its own method of measuring time.

3. **Evaluating Each Device**:
- **Sand Clock**: This device measures time by the flow of sand from one container to another. It is not very precise for small intervals.
- **Sundial**: This uses the position of the sun's shadow to indicate time, which is also not suitable for measuring small time intervals.
- **Water Clock**: This measures time based on the flow of water. While it can measure time, it is not as precise as needed for small intervals.
- **Pendulum Clock**: This device uses a swinging pendulum to keep time. The pendulum's regular motion allows for precise measurement of time intervals.

4. **Conclusion**: Among the devices listed, the pendulum clock is the most suitable for measuring small time intervals due to its consistent and regular motion.

5. **Final Answer**: The measurement of small time intervals became possible with the development of the **pendulum clock**.

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