Sally has a dog at home, so she knows about dogs. As she walks down the street, she sees an animal coming toward her. The animal has four legs, fur, and a tail. Ingrid knows that these are characteristics of dogs, but this animal is meowing, not barking. Sally's mom tells her that it's a cat. Now when Sally sees an animal with four legs, a tail, and fur, she will conclude it is a dog if it barks and a cat if it meows, illustrating Piaget's concept of _____.
a) accommodation
b) assimilation
c) operations
d) equilibrium

It is the concept of assimilation, what is assimilation, is it the process of understanding, One thing we humans have to do is to assimilate a concept and carry out its procedure to get a result.

Sally is trying to assimilate that not all four legs animals are dog , and she is categorizing them based on characteristics.as dog is to bark and cat meows, she is differentiating the two animals and in this process, that is were assimilation comes from. So therefore, it explains the concept of assimilation.