Answer:
A). Invisible ink isn’t really invisible at all.
Explanation:
The chief idea which the author aims to convey through the given passage would be that '<u>invisible ink is not actually invisible</u>.' This claim is substantiated through the descriptions asserting the type of inks(lemon juice, brown ink) that have been used to write such invisible content and also regarding how this invisible content can be visible(by holding the paper over candle's flame or using a chemical). This shows that the ink is not actually concealed completely. Thus, <u>option A</u> is the correct answer.
The correct answer among all the other choices is B.) Going 186 miles per hour, the most famous high-speed trains are the Bullet Train and the Train à Grande Vitesse. Thank you for posting your question. I hope this answer helped you. Let me know if you need more help.
