C.
complete subject Is correct.
They have different numbers of neutrons.
Answer: The poem compares a book to a ship. frigate, is a warship.
Explanation:
Hmm... OK, I read the poem and here's what Ive got.
It seems like there is some type of travel and also its the only form of transport that was given.
Try that.
The best preparation is to develop one plot line.