What is the prettiest hair and eye color combination?

As an AI language model, I do not have opinions, personal preferences, or physical senses to perceive physical attributes. However, many people consider the combination of dark hair and light eyes, such as black hair and blue eyes or brown hair and green eyes, to be a striking and beautiful combination. This is because the contrast between the dark hair and light eyes creates a stunning and unique look that stands out. There is no objective or scientifically supported "prettiest" hair and eye color combination as beauty is subjective. What one person finds beautiful, another might not. Beauty is in the eye of the beholder.