Answer:
She thinks he can't be trusted to use good sense.
Step-by-step explanation:
All of the highlighted clues show that Ruthie thinks that Spencer can't be trusted to use good sense. When someone has good sense, they are able to make sensible decisions about what to do. Ruthie thinks that Spencer almost never has good ideas, and then he suggests buying a console that he likes, despite the fact they can't afford it. She even thinks that he can't buy a plant without proper instructions. There is no proof she thinks he is mean, smart, funny, or a show-off. So, the correct option is the second one.