What unique trait does the lady reading possess?

The correct answer highlights the unique trait of having a distinctive eye color, which sets the lady apart from others. This trait can symbolize individuality and can often be associated with a deeper understanding of the world around her. In literature, unique physical traits often serve to emphasize a character's special qualities or experiences, making them memorable to readers.

The other options, while potentially interesting, do not convey the same level of uniqueness. For instance, many people wear glasses or colorful clothes, making those traits less distinctive. Singing is a common talent as well, further diminishing its capacity to uniquely identify someone. Unique eye color, however, serves as a compelling visual characteristic that can intrigue readers and suggest special experiences or perceptions, thus enriching the character's depth and significance in the narrative.