Task: Question Answering
Input (English): Question: A 70-year-old man presents, for a few months, without previous trauma, lumbar pain, difficulty walking, loss of strength and paresthesias in lower limbs, having to stop a few meters after starting it. The patient is increasingly inclining the trunk forward. What is the most likely diagnosis? 
 Options:  <1> Osteoporotic lumbar vertebral fracture. <2> Central herniated disc L5-S1. <3> Spondylodiscitis. <4> Stenosis of the lumbar canal. <5> Degenerative lumbar scoliosis.
Output (English): 4