Which of the following statements is FALSE?
1. The object is always placed to the left of the spherical mirror.
2. All distances parallel to principal axis are measured from pole of the mirror.
3. All distances measured to the right of the origin are taken as negative.
4. Distances measured perpendicular to and above the principal axis are taken as positive.

Correct option is B

The correct answer is (b) 3.
1. The object is always placed to the left of the spherical mirror: This is a correct statement. For the convention used in ray diagrams, objects are generally placed to the left of the mirror.
2. All distances parallel to the principal axis are measured from the pole of the mirror: This is also correct. In the case of spherical mirrors, all distances are measured from the pole, which is the central point of the mirror's surface.
3. All distances measured to the right of the origin are taken as negative: This is false. According to the sign convention for spherical mirrors, distances to the right of the origin (pole) are taken as positive. For example, the distance of the image from the mirror (for a concave mirror) is positive if the image is formed on the right side.
4. Distances measured perpendicular to and above the principal axis are taken as positive: This statement is correct. According to the sign convention, heights or distances above the principal axis are considered positive, while those below are negative.
Thus, the false statement is (3).