A central idea in The Code Book is the concern that much of the world's information is not secure. Which lines from the passage best support this central idea? Check all that apply.
a. it could be that the laws of mathematics forbid the existence of a significant shortcut
b. only a small fraction of the information flowing around the world is securely encrypted c. companies are already supplying shielding material that can be used to line the walls of a room
d. few of these people take adequate precautions in terms of privacy
e. law enforcers and anybody else with a curious mind can get their hands on more information

The lines that most effectively backs the key idea that "The C-o-d-e Book" proposes regarding the serious issue of global data not being secure" would be:

b). only a small fraction of the information flowing around the world is securely encrypted.

d). few of these people take adequate precautions in terms of privacy

e). law enforcers and anybody else with a curious mind can get their hands on more information.

The key idea that the text titled "The C-o-d-e Book" emphasizes is the issue of data across the globe not being secure which can be a potential threat.
The descriptions regarding a small number of information being encrypted, adopting precautions, and the power possessed by the authority or curious people to get acce-ss to these information substantiate this idea.
They further prove that the information is actually not secured and may be easily misused, hac-ked, or mishandled.

Thus, options b, d, and e are the correct answers.

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