Chromosome number edwards syndrome

how many chromosomes does an individual with trisomy 18 have?
A. 46
B. 23
C. 22
D. 45
E. 47

can someone explain why?


As we know that a normal human being has 23 pairs or 46 chromosomes in total. when drawing the karyotype the chromosomes are arranged in a pair of 2 in order of it’s descending size.
but, when there’s an abnormality present we can exceed the normal count of 46 chromosomes.
Edwards’s syndrome(Trisomy 18) being one of them that results in an extra copy of a chromosome no. 18.
Thus, a person with trisomy will have 47 chromosomes instead of 46.
Hope it helps:)