If y-coordinate of a point is zero, then this point always lies

Options

A. in I quadrant
B. in II quadrant
C. on X-axis
D. on Y-axis

Explanation

To solve the question "If the y-coordinate of a point is zero, then this point always lies...", we need to analyze the implications of having a y-coordinate of zero in the coordinate plane.

### Step-by-Step Solution:

1. **Understanding Coordinates**:
- A point in the coordinate plane is represented as (x, y), where 'x' is the x-coordinate (also called the abscissa) and 'y' is the y-coordinate (also called the ordinate).

2. **Setting the y-coordinate to Zero**:
- If the y-coordinate is zero, we can express any point as (x, 0). This means that the point has no vertical displacement from the x-axis.

3. **Identifying the Position of the Point**:
- The x-axis is the horizontal line where all points have a y-coordinate of zero. Therefore, any point with a y-coordinate of zero lies on this line.

4. **Examples of Points**:
- For example, if we take the point (1, 0), it lies on the x-axis.
- Similarly, the point (2, 0) also lies on the x-axis.
- Negative x-coordinates, like (-4, 0), also lie on the x-axis.

5. **Conclusion**:
- Since all points of the form (x, 0) lie on the x-axis, we conclude that if the y-coordinate of a point is zero, then this point always lies on the x-axis.

### Final Answer:
If the y-coordinate of a point is zero, then this point always lies on the **x-axis**.