Staring at the dog, James seemed to be a bit shocked or surprised, maybe even stunned.
"What is that?" James whispered.

Based on the story, which best explains why James was surprised when he saw the dog?

He has been focused on complaining and has not seen the dog.
He is tired from unpacking so many boxes.
He has returned to the kitchen to help his mother unpack.
He did not think the dog would come that far.