Question 7

(Multiple Choice)

Monotremes,like the duck-billed platypus,are egg-laying mammals covered in hair,have mammary and skin glands,have three ear ossicles,are diphyodont,and possess dentary-squamosal jaw articulation.Marsupials,such as kangaroos and koalas,are pouched mammals that have a vertical tympanic membrane in addition to possessing characteristics observed in monotremes.Eutherians,such as humans,are placental mammals that have a vertical tympanic membrane in addition to possessing characteristics observed in monotremes. What traits are shared derived traits for monotremes,marsupials,and eutherians?


A) mammary and skin glands, three ear ossicles, diphyodont, dentary-squamosal jaw articulation
B) vertical tympanic membrane, three ear ossicles, diphyodont, dentary-squamosal jaw articulation
C) three ear ossicles, diphyodont, dentary-squamosal jaw articulation, egg-laying
D) vertical tympanic membrane, three ear ossicles, diphyodont, placenta

Answer