Given below are two statements:

Statement I: In the RNA world, RNA is considered the first genetic material evolved to carry out essential life processes. RNA acts as a genetic material and also as a catalyst for some important biochemical reactions in living systems. Being reactive, RNA is unstable.

Statement II: DNA evolved from RNA and is a more stable genetic material. Its double helical strands being complementary, resist changes by evolving repairing mechanism. In the light of the above statements, choose the most appropriate answer from the options given below:

To determine the validity of the given statements, let us analyze the biological properties and evolutionary history of RNA and DNA step-by-step:

Analysis of Statement I:
1. First Genetic Material: There is strong scientific consensus that RNA was the first genetic material to evolve (often referred to as the "RNA World" hypothesis). Before DNA and proteins took over these roles, RNA carried genetic information and performed biochemical functions.
2. Catalytic Role: Unlike DNA, RNA can function both as genetic material and as a biological catalyst (ribozymes). For example, the catalytic part of the ribosome, which forms peptide bonds, is made of RNA.
3. Instability: RNA is chemically highly reactive and unstable compared to DNA. The presence of a reactive 2'-hydroxyl (-OH) group on its ribose sugar makes it susceptible to hydrolysis. Therefore, Statement I is correct.

Analysis of Statement II:
1. Evolution of DNA: DNA evolved from RNA as a more stable alternative for storing genetic information.
2. Stability and Repair: DNA lacks the reactive 2'-hydroxyl group (having a hydrogen atom at the 2' position instead, hence deoxyribose), making it chemically more stable. Furthermore, DNA is double-stranded with complementary base pairing, which allows one strand to act as a template for repairing damage in the other strand. DNA has evolved efficient repair mechanisms to resist changes and prevent mutations. Therefore, Statement II is also correct.

Since both Statement I and Statement II are correct, the most appropriate option is "Both statement I and statement II are correct".