Answer:
The slow pace establishes Snowball's intelligence by showing his work process.
Step-by-step explanation:
George Orwell's Animal Farm is an allegorical novel about the critique of communism especially that of the Soviet Union. This novel uses animals as characters to show how the fight for power leads to a much greater loss for the whole community.
The given excerpt from Chapter 5 of the book shows Snowball working on his plans for the windmill. His opponent Napoleon had not thought of such a plan, but still manages to influence others to take his side. The pattern of pacing in the given passage is slow, with the narrator/ writer revealing how Snowball works. Describing the room where Snowball worked on his plan, the writer also reveals that "he was closeted there for hours at a time". Moreover, "With his books held open by a stone, and with a piece of chalk gripped between the knuckles of his trotter, he would move rapidly to and fro, drawing in line after line and uttering little whimpers of excitement" which clearly shows his concentration and attentiveness to the work he's doing.
Thus, the correct answer is the last option.