Answer: Exons, Introns
Explanation:
The answer is Exons, Introns
When the base sequence of related genes from different species are compared, they base sequence of exons are highly conserved because the exons represent the coding region of the DNA or RNA that code for specific amino acids and because DNA replication, transcription and translation are of high integrity genes sequence are highly conserved.
Because Introns are non coding region and may be affected by mutation easily, the sequences of nucleotides in introns are much less conserved when compared to related genes.