Which feature is explicitly shown by a correctly exposed histogram?

A correctly exposed histogram is a graphical representation of the tonal values in a photograph, showing the distribution of shadows, midtones, and highlights. When the histogram displays an even distribution of light and dark areas, it indicates that the image contains a balanced range of tones without being overly dominated by shadows or highlights. This balance is key to achieving a well-exposed image, as it means that details are preserved in both the dark and bright areas without clipping or losing information.

In contrast, other options do not specifically relate to exposure. Sharpness refers to the clarity and detail of the image, which is not something indicated by a histogram. Consistent color temperature relates to the overall color balance in an image, which is not represented in tonal values. Lastly, a lack of highlights would suggest that the image is underexposed, leading to lost detail in bright areas, which is not characteristic of a well-exposed photograph. Thus, the even distribution of light and dark areas in a correctly exposed histogram is crucial for achieving a visually pleasing and technically sound photograph.