Why is emphasis created when a red fruit is placed among green leaves?

Correct answer: Through contrast of complementary colours

The governing concept is emphasis created by colour contrast. Red and green are commonly treated as complementary colours on the colour wheel, so their strong difference makes the red fruit visually distinct from the surrounding leaves. That contrast attracts the eye and establishes the fruit as a focal point. The question gives no evidence about unusual size, texture, or line similarity; therefore, option A is the best answer.