The correct answer is B. Brain
Step-by-step explanation:
The cranial cavity refers to the cavity in the head or skull that contains the brain, which is the organ that process information and controls most body function. Additionally, the cranial cavity is a rigid structure composed of different bones and it contains the meninges that are placed between the bones of the cranial cavity and the brain. According to this, if a doctor took images of the structures in the cranial cavity is because the doctor is examining and looking for abnormalities in the brain. After all, this is the main organ in this cavity.