Question

read the excerpt from \tools of the spymaster\.
james jays invisible ink did not become visible by heating. as he described it, his ink \would elude the generally known means of detection, and yet could be rendered visible by a suitable counterpart.\ jays invisible ink consisted of two chemicals. an agent used one chemical to write an invisible message. to read the message, the reader had to brush a second chemical on the paper, that chemical made the message visible. the two - bottle system, supplied by jay, gave washington the secure form of writing that he wanted.
which statement is best supported by text evidence from the excerpt?
heating was a generally known means of reading invisible ink.
james jay was widely considered a hero for his invention.
both the british and the americans used james jays invisible ink.
washington helped james jay develop the two - bottle system.

Explanation:

The text states that Jay's ink "would elude the generally known means of detection". Heating was a common way to read invisible ink (a "generally known means"), so Jay's ink was designed to avoid this. The other options have no support in the given text. There's no mention of Jay being a hero, the British using the ink, or Washington helping develop the system.

Answer:

Heating was a generally known means of reading invisible ink.