Final answer:
A smaller 'd' indicates better resolution, as it leads to larger angles of deflection in wave phenomena and allows finer details to be distinguished in imaging systems.
Step-by-step explanation:
When considering the term 'd' in relation to resolution, particularly in wave phenomena like light or sound, or in systems such as microscopes, a smaller 'd' typically indicates better resolution. For example, in the context of diffraction grating equations where 'd' represents the distance between slits, smaller values of 'd' lead to larger angles of deflection (θ), which results in higher resolution. This concept also aligns with the principle that wave effects like interference and diffraction are more noticeable when encountering smaller objects, hence a smaller 'd' improves the ability to distinguish fine details or separate close elements within an image. This is further supported by examples like the fact that image height resolution, represented by 'd' with a negative value (as per the given snippets such as (a) -0.233 mm), suggests that smaller features can be distinguished (resolution is finer) based on the size of rods and cones in the human eye.