Which of the following tests is considered a confirmatory test for brain death?

The correct answer is based on the understanding of brain death criteria and the role of various diagnostic tests. An electroencephalogram (EEG) assesses electrical activity in the brain and is critical in determining brain activity and function. In the context of brain death, a flat EEG, indicating no detectable electrical activity in the brain, supports the diagnosis of brain death.

While the other tests listed can provide important information, they do not serve as direct confirmatory tests for brain death. Nuclear brain scanning can show blood flow to the brain and may indicate whether the brain is functioning; however, it is not definitive for confirming brain death. Angiography visualizes blood vessels and can help determine circulation to the brain but is not specifically a confirmatory test for brain death. Somatosensory evoked potentials evaluate the functional status of the sensory pathways in the nervous system, but like the other options, it does not provide direct confirmation of brain death.

Thus, the EEG stands out as the confirmatory test because it directly demonstrates the lack of electrical activity, fulfilling an essential criterion in the clinical determination of brain death.