Help me please i have 4 more questions I rely on you guys bc you are smart beautiful people

c

Explanation:

B

Explanation:

It is B because the others are important because if they were easily decipherable, then they wouldn't choose the Navajo code. It's not C because if it was difficult even for the people who were hired to make and send codes, it'll take too much time to send messages. And it's not D because if the Japanese couldn't decipher the codes, they wouldn't have to use the Navajo code.

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.