The answer is the first option- "A-T"
James Watson<span> and</span>Francis Crick <span> discovered the three-dimensional structure of dna in 1953</span>
The RNA world hypothesis states that the earlier life-forms had relied only on RNA (Ribonucleic Acid) for the purpose of catalyzing the chemical reactions, and storing the genetic information. This hypothesis was proposed by Leslie Orgel, Carl Woese, and Francis Crick.
This hypothesis states that long before the living forms evolved to use DNA as the genetic storage material, the RNA molecules served the purpose of both storing the genetic information and carrying out catalysis, but because of its instability, DNA evolved.
Hence, the answer is RNA world hypothesis.
Answer:
Show the client pictures that illustrate how a colostomy looks and functions.
Explanation:
