A Coordinate plane has two perpendicular number lines. The vertical line is the y-axis and the horizontal line is the x-axis. The point of intersection between this line is called "Origin" and it's at the point (0,0).
There are four sections in a Coordinate plane which are called "Quadrants". See the drawing below to see their location in the Coordinate plane:
Having the point:
You can notice that, the x-coordinate is positive and the y-coordinate is also positive. This means that the point (4,1) is located in the QUADRANT I.
Therefore, the answer is: b. I