01 Why can readability be weak in a poster even when hue contrast is strong but value contrast is low?
Answer and explanation
Correct answer: A. The text and background may have similar light-dark values.
Explanation: The governing concept is legibility through value separation. Readers often recognise text most easily when it differs clearly from its background in lightness and darkness. Strong hue contrast may still appear weak at a distance, in poor light, or to some viewers when the values are similar. A is correct; B and C ignore value, while D is irrelevant.