Answer:
The author writes with great scientific detail.
Step-by-step explanation:
Simon Singh's "The Code Book" presents a detailed account of the history of cryptography through the tracing of its evolution and how secrecy came to be. The idea of a secret code for messages is what intrigues everyone and thus, this book delves into the how of such coded messages.
As seen in the given excerpt, the author Simon Singh states how scientific details such as "p and q" and the factoring of "the public key, N" are all processes to learn about Alice's private key. The inclusion of details such as "check[ing] each prime number one at a time to see if it divides into N" are all scientific approaches that will lead to the understanding of the private key.
Thus, the correct answer is the last or fourth option.