Ribose sugar is present in

The discovery of which of the following in $1980$ led to the term '$RNA$ World' for evolution?

Given below are two statements:
Statement $I$: $RNA$ mutates at a faster rate.
Statement $II$: Viruses having $RNA$ genome and shorter life span mutate and evolve faster.
In the light of the above statements,choose the correct answer from the options given below:

How many nucleotides does a transfer $RNA$ $(tRNA)$ molecule typically contain?

Which of the following is $NOT$ a function of $RNA$?

Which of the following $RNA$ is non-functional?