Answer: the concrete oprational stage
Explanation: According to Piaget, this stage goes from approximately 7 yrs old to 11 yrs old and allows the child to overcome their egocentric thinking. This means that they can now understand reversibility of things, for example that a litre of water will be the same independently of the bottle or container; this also allows the child to be able to "put themselves in someone else's position".
This child in particular is now able to understand that her babysitter is also an student due to having acquire this ability.
Oak tree is an inanimate object, it stays where-ever it was before and after the movie.
The purpose of speech is to pass knowledge down through generations and to commuinicate to others
