**Explanation:**

To understand why the correct answer is option 'B', let's first review the four quadrants on the coordinate plane:

1. **Quadrant I:** It is located in the upper right portion of the coordinate plane where both the x-coordinate (horizontal) and y-coordinate (vertical) are positive.
2. **Quadrant II:** It is located in the upper left portion of the coordinate plane where the x-coordinate is negative and the y-coordinate is positive.
3. **Quadrant III:** It is located in the lower left portion of the coordinate plane where both the x-coordinate and y-coordinate are negative.
4. **Quadrant IV:** It is located in the lower right portion of the coordinate plane where the x-coordinate is positive and the y-coordinate is negative.

Now, let's consider a point with both coordinates positive. This means that the x-coordinate is positive (greater than 0) and the y-coordinate is also positive (greater than 0).

Since the x-coordinate is positive, the point cannot lie in Quadrants II or III, as these quadrants have negative x-coordinates. Therefore, the point must lie in either Quadrant I or Quadrant IV.

However, since the y-coordinate is also positive, the point cannot lie in Quadrant IV, as this quadrant has a negative y-coordinate. Therefore, the only quadrant where a point with both positive coordinates can lie is Quadrant I.

Hence, the correct answer is option 'B' - the point lies in Quadrant I only.

I quadrant