The correct answer is polysomy.
This is one of the abnormality of chromosome. This condition can be seen in the species such as fungi, insects and mammals. In this the organisms has atleast one extra chromosome rather than normal. Polysomy is a type of aneuploidy. Polysomy may lead to physical malfunction and undeveloped mental condition. For example : Trisomy in human causes a syndrome called Down Syndrome.
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