The correct answer would be b.
You want to test them on what they should know, and see if they are on the level they should be at.
A seven letter word containing thousands of letters - a mailbox.
The word mailbox has 7 letters, and it contains thousands of letters - just not the letters from the alphabet, but rather a form of a paper message.
I typed it but it was coming rude words.
So, I took screenshot for your answer.
<h3>PLEASE MARK ME BRAINLIEST.</h3>