If a person had an extra chromosome in his cells and he survives. What will be the possible outcome?

That is not a simple answer, because the outcome of such a genetic problem depends on which of the 23 chromosomes is duplicated. If it is chromosome 21, then the person will have Down's syndrome, but other duplicate chromosomes may result in XYY syndrome (duplication of a sexual chromosome), Edward's syndrome (trisomy of chromosome 18), etc. See the link below for more information.

One consequence of these chromosomal abnormalities is usually infertility, because the gametes produced by these individuals will be abnormal and unable to match with normal gametes.

From what I can remember ( which admitedly isn't much ),
whether we're talking about somatic OR sex chromosomes, there will undoubtably be physical and/or mental abnormalities.
It is my humble opinon that, IF the individual in question could
even HAVE offspring, they may not all have an extra chromosome. I know this answer isn't as cool as the others
but, I am , after all, a "bear of little brain with a head full of fluff".

Something else. With Down's, chromosome 21 is hard to distinguish from 22. Is it really definite which of these is responsible for the syndrome?

in such a case, he'll have down's syndrome, klienfeilter's syndrome or turner's syndrome depending upon whether the extra chromosome is an autosomal one or sexual 1. n his poffspring may or may not have an extra chromosome.
the most probable ans from ur list looks like II n onlyII.
cya then
dee

he will be retarded. like down's syndrom or

I'm thinking C. Due to trisomy, there will not be homologous pairing thus no successful meiosis for viable gametes. And usually the extra chromosome causes genetic defect that makes survival a challenge for the individual, much less mate. The extra chromosome could cause excess protein synthesis, which could be hormones or peptides that could affect the cerebellum.

He will have Down's Syndrome