1, c, self-centered. Egocentrism means that an individual thinks that the world exists for him. Lily only knows herself, not her brother, just because she can't understand the world from her brother's point of view. Conservation means that no matter how the shape of an object changes, its mass remains the same. In this case, Lily was not asked whether Lele wore a hat or had any other changes, so it had nothing to do with conservation.

2, b, preoperative stage (2-7 years old). Children in the pre-operation stage begin to express what they have experienced with sounds, images and symbols. And the road map is a symbol of the road you have traveled in your mind.

The "picture flicker" above is obviously wrong. The perceptual motor stage is the cognitive development stage of children aged 0-2.