Which of the following principles suggests that physical properties of substances,such as volume,number,and mass,remain constant despite changes in their shape or appearance

A)  centration
B)  conservation 
C)  egocentrism
D)  object permanence

Conservation is the principle that states that physical properties of substances remain constant despite changes in their shape or appearance. This concept typically develops around the age of 7-8 years old, during the concrete operational stage of cognitive development, according to Piaget's theory. The other principles listed (centration, egocentrism, and object permanence) are also important in this stage but do not specifically address the idea of the constancy of physical properties.