<prompt> Which of the following is a skeletal muscle relaxant that acts as a central a2 adrenergic agonist:TizanidineBrimonidineChlormezanoneQuinine  <response>: Tizanidine and brimonidine are alpha2 adrenergic agonists. Tizanidine is used as a centrally acting muscle relaxant whereas brimonidine is used topically for the treatment of glaucoma. Chlormezanone is a centrally acting muscle relaxant that acts by inhibiting the spinal internuncial neurons. Quinine is a directly acting peripheral muscle relaxant. 