Which two disorders are autosomal dominant according to the source material?

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Autosomal dominant inheritance means that a single mutated copy of a gene on an autosome is sufficient to cause the disorder, and each affected person typically has an affected parent with about a 50% chance of passing it to offspring. Huntington disease is the classic autosomal dominant neurodegenerative disorder, caused by a CAG repeat expansion in the HTT gene, with transmission often seen across generations. In the source material, primary progressive aphasia is described in familial contexts as following an autosomal dominant pattern, with certain genetic forms linked to frontotemporal dementia that can present as language impairment. So, the material treats Huntington disease and PPA as autosomal dominant. The other options mix conditions that are not both autosomal dominant (many are autosomal recessive, or have different inheritance patterns like X-linked), which is why they don’t fit the stated pattern.