It's hard to tell what the options are lol, but I'd say Mysterious.
The narrator hears tapping -- neither he nor the reader knows what it is. The core of the word mysterious is <em>mystery</em>, and this provokes a question our minds; what could it be?
Standardized testing is a type of testing that holds all students to a certain educational standard and tests how they measure up to said standard.
The root of the word digest is dig
Answer: designed by Kipling and Graber to be read out aloud to a child
Explanation: The crab became too big for his shell.
When you have different things