Match list I with list II and select this correct answer using the codes given below the lists.
`{:(,"List - I",,"List - II"),((p),"Nucleic acids",1.,DNA),((q),"Uracil",2.,"Hormones"),((r),"Thymine",3.,"Polynucleotides"),((s),"Double - helix structure",4.,"RNA"):}`

Options

A. `(p)-4,(q)-3,(r)-1,(s)-1`
B. `(p)-3,(q)-4,(r)-1,(s)-1`
C. `(p)-3,(q)-1,(r)-4,(s)-1`
D. `(p)-3,(q)-1,(r)-1,(s)-4`

Answer

To solve the matching question, we need to pair the items from List I with the correct items from List II based on our knowledge of biology and chemistry, particularly focusing on nucleic acids and their components.

### Step-by-Step Solution:

1. **Identify P (Nucleic acids)**:
- Nucleic acids are macromolecules that include DNA and RNA. They are made up of polynucleotides.
- **Match**: P (Nucleic acids) matches with 3 (Polynucleotides).

2. **Identify Q (Uracil)**:
- Uracil is one of the four bases found in RNA. The bases in RNA are adenine (A), guanine (G), cytosine (C), and uracil (U).
- **Match**: Q (Uracil) matches with 4 (RNA).

3. **Identify R (Thymine)**:
- Thymine is one of the four bases found in DNA. The bases in DNA are adenine (A), guanine (G), cytosine (C), and thymine (T).
- **Match**: R (Thymine) matches with 1 (DNA).

4. **Identify S (Double-helix structure)**:
- The double-helix structure is characteristic of DNA, while RNA typically exists as a single-stranded molecule.
- **Match**: S (Double-helix structure) matches with 1 (DNA).

### Summary of Matches:
- P → 3 (Nucleic acids → Polynucleotides)
- Q → 4 (Uracil → RNA)
- R → 1 (Thymine → DNA)
- S → 1 (Double-helix structure → DNA)

### Final Matching:
- P: 3
- Q: 4
- R: 1
- S: 1

### Conclusion:
The correct answer based on the matches is option number 2.