Did you miss the word illusion in there?
Nope. Did you miss the word appear?
No I didn't, however I know how English works. The sentence clearly says that it is an illusion that "the Sun appears bigger". This means it does not appear bigger, it's just an illusion. Did you also miss the sentence structure? It did not just say "The sun appears larger" it said "That the sun appears larger" as in they are referring to the statement "The sun appears larger" and go on to explain that it is incorrect.
Evidently, you do not know how English works.
David Copperfield caused an elephant, that was appearing in front of my eyes, to disappear.
But it was an illusion.
Illusions are fundamentally based on how things appear.
Go ask a 5th grader to explain it to you, if they are normal they would know this.
Copperfield made the elephant disappear. One second you saw it, the next you didn't. It may have still been there, but he arranged it so you could no longer see it.
The sun does not appear larger on the horizon, you just think it does, but you can easily verify that it doesn't by doing the experiment she suggested.
I give up. Go find that 5th grader.