What is the most correct meaning of DNA integrity?

Correct answer: How intact or broken DNA is

DNA integrity means the physical completeness and quality of a DNA sample. DNA with good integrity is largely intact, with long molecules and little fragmentation. DNA with poor integrity is broken into many smaller pieces because of physical shearing, nucleases, heat, or unsuitable handling. Therefore, option B correctly describes integrity as how intact or broken the DNA is. Taste, ethanol quantity, and tube colour do not define the condition of the DNA molecule.

Integrity can be examined by methods such as gel electrophoresis. A mostly intact genomic DNA sample commonly appears as a high-molecular-weight band or compact region, whereas degraded DNA produces a smear toward smaller sizes. The test does not measure the taste of DNA or the colour of a tube. It gives information about molecular fragmentation and preservation. Thus the supplied answer B follows directly from the biological meaning of DNA integrity and is correctly explained.