Who first suggested the idea of circular flow of genetic information?

Statement-$I$: The split gene arrangements represent probably an ancient feature of the genome.
Statement-$II$: Introns or intervening sequences do not appear in mature or processed $\text{RNA}$.

Define the following terms: Replication fork and Transcription.

Match the following columns:

Column-$I$	Column-$II$	Column-$III$
$(1) \ 1952$	$(a)$ Watson and Crick	$(i)$ Double helix model of $DNA$
$(2) \ 1928$	$(b)$ Friedrich Miescher	$(ii)$ Proof that $DNA$ is genetic material
$(3) \ 1869$	$(c)$ Griffith	$(iii)$ Nuclein
$(4) \ 1953$	$(d)$ Hershey and Chase	$(iv)$ Transforming principle

Which one of the following pairs is not correctly matched?

By using the diagram,select the correct option for $X$ and $Y$.