Answer: A. Extraordinarily important.
Explanation: Based on the information presented in the excerpt, we can infer that the information in the wireless message was extraordinarily important, because all the signs the characters give each other without even saying a word, like that the twitching of "Blinker's" eyes became more pronounced as he was reading the message and also the seriousness of de Grey while he delivered the message.
I believe the correct answer is to help the reader visualize a view where water and sky are difficult to tell apart.
The author is trying to portray an image where the water and the sky are somehow blending into each other - you can't tell where one ends and the other one begins, because both items are colored similarly - various shades of blue.
B) Her entry from the side underlines her devious mannerisms. I believe
Protagonists is a good guy/ main character