Down syndrome is caused by trisomy 21.
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NEET UG 2020 — Biology Genetics
medium
mcq
2020
Official previous-year question
Verified 30 May 2026.
Question
Down syndrome is due to
Options
- AMonosomy of chromosome 21
- BTrisomy of chromosome 21
- CTrisomy of chromosome 18
- DDeletion in chromosome 5
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