uk-dgm MCQ (SBA): Dementia with Lewy Bodies Diagnosis

A 74-year-old woman is referred to the memory clinic. She reports a 2-year history of fluctuating alertness, recurrent well-formed visual hallucinations of people in her bedroom, and occasional episodes of stiffness. Her husband reports she frequently shouts out and thrashes in her sleep. MoCA is 21/30. There is mild bilateral upper limb rigidity. What is the MOST likely diagnosis?