Final answer:
Lennie's behavior in the first chapter can be described as forgetful with a liking for soft things and a gentle nature, which aligns with option C from the provided choices.
Step-by-step explanation:
The correct option that describes three things the reader learns about Lennie's behavior in the first chapter is C) He forgets things easily, he likes to pet soft things, he has a gentle soul. This is seen in John Steinbeck's novel Of Mice and Men, where Lennie Small displays a childlike demeanor, with a fascination for soft things, such as mice and rabbits, which he inadvertently harms due to his lack of awareness of his own strength.
His forgetfulness and his tendency to hold onto instructions given by his companion George are also notable characteristics. Lennie can be described as a gentle soul who does not inherently desire to hurt anyone or anything, but his mental capacity and immense physical strength pose a significant challenge for him in understanding the consequences of his actions.