Correct option is B
Tolerance is defined as the total permissible variation in size, not just a single deviation. When a shaft has a basic size of 75 mm and only a +0.02 mm variation is given, it is generally interpreted as a bilateral tolerance, meaning the dimension can vary both above and below the basic size. So, the limits become +0.02 mm and −0.02 mm. Therefore, total tolerance = (+0.02 − (−0.02)) = 0.04 mm. Tolerance is always expressed as a positive value because it represents a range, not direction. Hence, option b is correct
