DNA is the hereditary material of the cell which provides the genetic information. This fact was established by Martha Chase and Alfred Hershey individually in the year 1959.

Identify the labels marked A, B, C, D in a sequence in the illustrated diagram.

A student grew virus in three different media containing ${\mathrm{P}}^{32}, {\mathrm{S}}^{35}$ and DNAase separately and allow this virus to attack to E. coli. The series of observation made by the students are as follows:

a) ${\mathrm{P}}^{32}$ labelled phage particles were produced in E. coli.
b) ${\mathrm{S}}^{35}$ containing phage particles were produced E. coli.
c) Phage particles were observed in E. coli.

d) ${\mathrm{P}}^{32}$ was not observed in phage particles produced by E. coli.
e) ${\mathrm{S}}^{35}$ was not observed in phage particles produced by E. coli.

The correct observations are

A bacterial strain $\mathrm{S}$ was heat killed. Another strain $\mathrm{R}$ (living) was taken and mixed with this S strain. This mixture of $\mathrm{S}+\mathrm{R}$ strains were injected into mice. Which of the following are observed by Griffith?

I. The cells of $\mathrm{S}$ strain were dead in dead mice.

II. The bacterial cells without polysaccharide coat are transformed into virulent strain in the injected mice.

II. Griffith could not find living $\mathrm{S}$ strain in the body of dead mice.

IV. Griffith could find living $\mathrm{S}$ strain in the body of dead mice.

The correct combination is: