Acertain mutation in the human chromosome number 9 causes part of the chromosome to break and reattach itself in a reverse manner. what kind of mutation is this?
a. chromosomal duplication
b. chromosomal inversion
c. chromosomal deletion

The answer is b. chromosomal inversion

Chromosomal inversion is a point mutation which means the mutation only involves a single chromosome. This happens when two breaks occur within the strand freeing the single chromosome to move. The single chromosome that breaks off rotates 180 degrees before reattaching. The chromosome "inverts" itself, that's why the mutation is called inversion.