Which of the following has definite length ?

Options

A. A line
B. A line segment
C. A ray
D. None of these

Answer

To determine which of the following has a definite length, let's analyze each option step by step.

### Step 1: Understand the Definitions
- **Line**: A line extends infinitely in both directions. It does not have a fixed length.
- **Line Segment**: A line segment has two endpoints and a fixed length between those two points.
- **Ray**: A ray starts at a point and extends infinitely in one direction. It does not have a fixed length.
- **None of these**: This option implies that none of the above have a definite length.

### Step 2: Analyze Each Option
- **Option A: Line**
- A line has no endpoints and extends infinitely. Therefore, it does not have a definite length.

- **Option B: Line Segment**
- A line segment has two endpoints, which means it has a specific length. For example, it could be 5 cm, 10 cm, etc. This is a definite length.

- **Option C: Ray**
- A ray starts at one point and extends infinitely in one direction. Thus, it does not have a definite length.

- **Option D: None of these**
- Since we have identified that the line segment does have a definite length, this option is incorrect.

### Step 3: Conclusion
From the analysis, we can conclude that the only option that has a definite length is:
**Option B: Line Segment**