A lumbar puncture would be contraindicated in a 68-year-old woman suspected of having Alzheimer's disease if she has a history of which of the following?

Choice A reason: Acute lower back pain may complicate patient positioning or increase discomfort but is not an absolute contraindication to lumbar puncture. Choice B reason: Osteoporosis increases fracture risk but does not directly contraindicate lumbar puncture; precautions can be taken. Choice C reason: This is the correct answer. Increased intracranial pressure is a contraindication because removing cerebrospinal fluid in the setting of elevated intracranial pressure can precipitate brain herniation, which is life-threatening. Choice D reason: Decreased cardiac output may increase procedural risk but is not an absolute contraindication to performing a lumbar puncture.