Which of the following statements regarding the numerical chromosomal aberration is incorrect?

• A. It refers to any variation in the number of chromosomes caused by certain irregularities during cell division.
• B. A person is heteroploid if they have chromosome numbers other than true monoploid or diploid numbers.
• C. Change in the number of chromosomes, but not in a set is called euploidy.
• D. A euploid organism carries an exact multiple of the basic chromosome number.

Answer: (C)