I think the answer for this Question is DNA
Answer:
a) snRNA
Explanation:
The association of small nuclear RNA (snRNA) and some specific proteins forms small nuclear ribonucleoprotein complexes. Some complexes are spliceosomes, molecular machines -made up of a snRNA and about 80 proteins- that remove introns from pre-mRNAs via successive phosphoryl transfer reactions.
It's a deep rift valley which runs along the middle of the ridge along almost its entire length.