Seven-Year-Old Jerusha Is Always Upset When Her Older Brother Is

Multiple Choice

Seven-year-old Jerusha is always upset when her older brother is given two slices of pizza but she gets only one. Until recently, Jerusha's mother could make her happy by cutting her pizza slice in half so that she now had two, but Jerusha has come to realize that cutting one slice in half isn't the same as getting two slices that are each the size of her brother's. Jerusha now understands

A) sensory operations.
B) concrete operations.
C) conservation.
D) object permanence.
E) Irreversibility.