Concept: The word “wane” means to become weaker or decrease in strength or intensity.
Explanation:“Wane” describes a gradual loss of power, importance, or brightness.
For example, the moon wanes as its visible light decreases.
Among the options, “decline” also means to become smaller, weaker, or less.
“Disappear” means to vanish completely.
“Change” is too general and does not match the exact meaning.
“Disperse” means to scatter in different directions.
Therefore, the word that best matches “wane” is “decline”.
Answer: D. decline