The cervical spine has how many vertebrae?

Correct Answer: C

Rationale: The correct answer is C: 7. The cervical spine consists of 7 vertebrae, labeled as C1 to C7. Each vertebra plays a vital role in supporting the head and facilitating neck movement. C1 is known as the atlas, C2 is the axis, and C3 to C7 are structurally similar cervical vertebrae. These vertebrae house the spinal cord and provide flexibility for head movements. Choices A, B, and D are incorrect because the cervical spine does not have 2, 5, or 8 vertebrae. It is crucial to understand the anatomical structure of the spine to determine the correct number of cervical vertebrae.

Correct Answer: C

Rationale: The correct answer is C: Stenosis of aqueduct of Sylvia. This condition causes obstruction in the Sylvian aqueduct, leading to hydrocephalus with enlarged lateral and third ventricles but a normal fourth ventricle. Holoprosencephaly (A) is a midline defect, not specific to ventricle enlargement. Disorder of prosencephalon (B) is too broad and doesn't specifically address ventricle enlargement. Meningitis with blockage of arachnoid villi (D) is typically associated with communicating hydrocephalus, not specific to the aqueductal stenosis pattern seen in this case.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.