"It's likely the publisher/designer/editor/writer of the book just looked up 'eye chart' and found this one, which is a joke chart that has been found on t-shirts, etc."
"I agree," wrote another person. "It was probably an innocent mistake, since the preparer of this ESL material is probably Korean."
One of my daughters contacted me yesterday. "Dad. We did a search. Guess what?"
So I did a search myself on Google: eye chart.
Here's what came up, first thing, top of the page: