Bill is a designer at a toy company. One of his ideas for a toy is a clown-face mobile painted in bright colors. Each battery-operated clown face will, when pulled, play a different song and the eyes will light up. This game is most appropriate for children in the stage of cognitive development.

Sensorimotor stage of cognitive development.

Explanation:

As developed by Piaget, the sensorimotor stage involves the use of the infant's senses and motor abilities to understand the world around them. Be it seeing, sucking, hearing, touching, etc. they begin to discover, through trial and error, their world. Therefore, the toy would have sound cues (would exercise the infant's hearing) colour cues (it's seeing, glancing, differentiating colours, etc.) and when pulled, both sound and colour would change. The infant would be able to exercise plenty of his sensorimotor skills with this toy, making it a very appropriate one for their development.  

Sensorimotor.

Explanation:

The Sensorimotor stage of cognitive development is one of the the four stages of the cognitive development stages developed by Piaget. The Sensorimotor stage of cognitive development is the first stage out of the four cognitive development stages and it do happen in children between the years of birth till around 2 years of age.

The Sensorimotor stage of cognitive development is a stage in which children learn things in the environment or surrounding by making use of their sense organs.

So, children that will use the toy will make use of their sense organs for instance the skin for feeling, eyes for vision and ears for hearing.