Answer:
D). Definition 4.
Step-by-step explanation:
The word 'illusion' denotes 'a misapprehension or a belief that is factually not true.' In the given question, 'definition 4' demonstrates the entry that most aptly describes the word 'illusion' in the sentence stated below. Since the word 'illusion' literally means 'a deceptive appearance', it is rightly described in definition 4 as 'a perception..different from the way it is in reality.' Therefore, the sentence implies that 'the stationary boxes together created a deceptive/false impression(illusion) as if it were moving' which was actually not true but rather a false perception. Thus, option D is the correct answer.