The proper noun that should capitalized is Christie
The simple subject is the main word of the subject, without any adjectives or modifications, one that would be enough to form a correct sentence; and the complete subject is one with all the adjectives and modifiers.
For example: B:
Dinosaurs: simple subject
<span>Large and small dinosaurs: complete subject.
In option C </span>the simple subject is the complete subject: "Cory"