A 4-year-old boy has had constipation and painful defection since birth. Impacted fecal matter is palpable in the lower abdomen. Examination of tissue obtained on biopsy of the rectum shows absence of cells of the myenteric plexus. The most likely cause is a defect in which of the following developmental events?
A) Alar plate maturation
B) Anterior neuropore closure
C) Neural crest migration
D) Paravetebral ganglion formation
E) Posterior neuropore closure
F) Recanalization of the bowel

C - Neural Crest Migration

i agree with arivedreci, ans is C

I Also Agree.

Definitively, the answer is "C" - failure of Neural Crest Migration.

Ccccccccccccccccccccc

Ccc Is The Right Answer

I am going with the majority, its Neurocrest ;Hirschsprungs agangliosis. feculent vomit, distention with obstipation males>>>>females 0-2yrs. the give away is the abscence of the nerve cells.!!!!!in the Q.

it is definitely c

followup question:
What abnormality you can see if there is a is failure to close the Posterior neuropore closure?
2- and what about the anterior one?

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