This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Chromosome inversion is: 
Select and explain. 
A. A portion of the chromosome is missing or deleted, B. A portion of the chromosome is duplicated, resulting in extragenetic material, C. A single chromosome undergoes breakage and rearranges within itself, D. A portion of one chromosome has been deleted from its normal place and inserted into another chromosome
C: A single chromosome undergoes breakage and rearranges within itself
Answer: C: A single chromosome undergoes breakage and rearranges within itself 
Explanation: Inversion: Occur when there are two interstitial of a single chromosome breaks in and the segment reunites & rearranged after a complete turnaround.
Option A - Deletion e.g. Wolf-Hirschhorn syndrome, Jacobsen syndrome, also called the terminal IIq deletion disorder.
Option B - Duplication - e.g. Charcot-Marie-Tooth disease type 1A
Option D - Insertion
Other structural disorders of chromosomes:
Rings:

A portion of a chromosome has broken off and formed a circle or ring.
This can happen with or without loss of genetic material.

Isochromosome:

Formed by the mirror image copy of a chromosome segment including the centromere.

Aneuploidy:

Numerical disorder of chromosomes.
Missing a chromosome from a pair is called monosomy and presence of more than two chromosomes of a pair (trisomy, tetrasomy, etc.)