Which bone is the longest and strongest bone in the human body?

Correct Answer: B

Rationale: The femur (thigh bone) is the longest and strongest bone in the human body, supporting significant weight and muscle forces during movement. The cranium is a collection of bones, not a single bone, while the tibia and radius are shorter and less robust.

Correct Answer: A

Rationale: The brain resides in the cranial cavity, a well-defined space within the skull formed by the cranial bones. 'Hole' and 'pit' are vague and not standard terms for this structure.

Correct Answer: B

Rationale: Vertebrae increase in size from top (cervical) to bottom (lumbar) to support greater body weight and stress. Cervical vertebrae are smallest, thoracic intermediate, and lumbar largest, reflecting their load-bearing roles.

Correct Answer: B

Rationale: Ribs 11 and 12 are 'floating ribs,' lacking any attachment to the sternum, unlike false ribs (8–10), which connect indirectly via cartilage. 'Loose' is not a standard term here.

Correct Answer: A

Rationale: The ulna is slightly longer than the radius and features the olecranon (elbow projection) and coronoid process (anterior projection), forming the elbow joint with the humerus. The radius lacks these.