Because it is present in the earliest cell that lived in earth
<span>The main difference between DNA and RNA is that DNA contains double-stranded molecules and RNA contains single-stranded molecules. DNA stands for deoxyribonucleic acid and RNA stands for ribonucleic acid. Both DNA and RNA carry genetic information, but there are a few major differences between them. DNA consists of the sugar deoxyribose, and RNA contains the sugar ribose. Ribose contains one more -OH group than deoxyribose. Another difference is that DNA is stable under alkaline conditions while RNA is not stable.</span>
The combination of genetic material from two different individuals/parents the offspring gets half the traits from the mother and the other half from the father hope this helps
According to the principle of superposition the youngest rock formed lies at the upper layer and the oldest rock are found at the lowest of all the layers. The principle of superposition states that the layer of rock that is formed first lies at the bottom and the layer that is formed upper after that lies at the upper and is the newest layer of rock.
