The nurse understands that which form of multiple sclerosis shows a gradual, continuous worsening of neurological function from the onset of the disease?

Rationale: A. Secondary progressive MS initially begins as relapsing-remitting, with periods of symptom flare-ups followed by partial recovery. Over time, the disease may transition into a phase of steady progression, but this is after an initial relapsing course, not from disease onset. B. Progressive-relapsing MS is characterized by steady neurological decline from onset, with occasional superimposed relapses. However, it is a rare subtype. Although it has continuous worsening, the hallmark is the presence of distinct relapses, unlike primary progressive MS, which is purely progressive without relapses. C. Relapsing-remitting MS is the most common form and is characterized by episodes of new or worsening neurological symptoms (relapses) followed by partial or complete recovery (remissions). Neurological function does not worsen continuously, making this inconsistent with the scenario. D. Primary progressive MS involves gradual, continuous neurological deterioration from the onset of symptoms, without distinct relapses or remissions. Patients experience steady accumulation of disability, often involving spinal cord symptoms such as weakness and spasticity. This subtype represents 10–15% of MS cases and typically does not respond as well to disease-modifying therapies compared with relapsing forms.