The correct answer is: 2.5%
The vast majority of the human genome (97.5%) is comprised of non-coding DNA with different functions. Non-coding DNA includes telomeres, introns, non-coding RNA genes and gene regulatory sequences.
• Telomeres-ends of DNA with protective role (prevents shortening of DNA),
• Non-coding RNA genes-e.g. genes for tRNA,
• Gene regulatory sequences such as promoter, enhancers and silencers.
