Huntington disease is an autosomal dominant disorder that leads to progressive degeneration of brain cells. there is no effective treatment for the disorder and individuals usually die in their 40s or 50s, 10 to 15 years after the onset of symptoms. which of these statements about huntington disease is true?

-huntington disease can only be inherited when a parent is showing the trait.
-huntington disease usually appears during middle age.
-as an autosomal dominant disease, huntington disease is expressed only if both parents carry the trait.
-huntington disease usually skips a generation.

An 80-year-old woman comes to the urgent care clinic with dyspnoea on exertion. on physical examination, her blood pressure is 100/70, and her pulse is 75. she has no pulsus paradoxus. her jugular veins are distended, and she has distant heart sounds. in addition, she has extra third and fourth heart sounds. her liver is enlarged, and she has pedal oedema. she has occasional premature ventricular contractions on her electrocardiogram. a chest x-ray reveals clear lung fields with a dilated cardiac silhouette. her echocardiogram reveals ventricular walls with a "speckled pattern". which of the following is the most likely diagnosis? - alcoholic cardiomyopathy- amyloidosis- haemochromatosis- tuberculosis- viral myocarditis