How Does One Assess an Infant's Grasp of Object Permanence

How does one assess an infant's grasp of object permanence?

A) Give a baby a new object, something the baby has never seen before, and observe how the baby plays with it.
B) Remove an object from a baby's view and observe whether or not the baby pursues the object.
C) Take an object away from a baby and place it among two or three other objects. See if the baby can select the familiar object.
D) Tell the baby "bye-bye" and then see if the baby waves bye-bye to you.