<prompt> Which of the following is X-linked recessive?Duchenne muscular dystrophyHypophostemic ricketsMarfans syndromeDowns syndrome  <response>: Ans. a Duchenne muscular dystrophyRef: R 9thpg 142a. Duchenne muscular dystrophyX-linked recessiveb. Hypophostemic ricketsX-linked dominantc. Marfans syndromeAutosomal dominantd. Downs syndromeChromosomal trisomy 