Which of the following is considered 'Add Power' in optics?

'Add Power' refers specifically to the additional magnifying power needed for near vision, which is most commonly associated with reading correction. As individuals age, they often experience presbyopia, a condition where the eye's ability to focus on close objects diminishes. In such cases, an additional lens power, typically referred to as 'Add Power,' is prescribed to assist with close tasks like reading.

In this context, reading correction provides the necessary power for individuals to see objects up close clearly. It is distinct from other optical corrections, such as distance correction, which pertains to vision at far distances. Astigmatism power, on the other hand, addresses the distortion caused by irregular curvature of the eye's lens, rather than providing additional power for near vision tasks. Base curve measurement is related to the curvature of the lens and its fit but does not pertain to visual acuity itself.

Therefore, the choice related to reading correction accurately captures the essence of 'Add Power' in optics, illustrating its critical role in accommodating near vision needs.