Answer to Question 1
ANS: C
Most infants can pull themselves to a standing position at age 9 months. Any infant who cannot pull to a standing position by age 11 to 12 months should be referred for further evaluation for developmental dysplasia of the hip. At 6 months, the infant has just obtained coordination of arms and legs. By age 8 months, infants can bear full weight on their legs.
Answer to Question 2
ANS: C
During the first 6 months of life, infants believe that objects exist only as long as they can see them. When infants search for an object that is out of sight, this signals the attainment of object permanence, whereby an infant knows that an object exists even when it is not visible. Between ages 8 and 12 weeks, infants begin to respond differentially to their mothers. They cry, smile, vocalize, and show distinct preference for their mothers. This preference is one of the stages that influence the attachment process, but it is too early for object permanence. Recognizing familiar objects is an important transition for the infant, but it does not signal object permanence. The ability to understand cause and effect, such as pulling on a string to secure an object, is part of secondary schema development.