Step 1: Understanding the acidity of DNA and RNA.
DNA and RNA are acidic due to the presence of phosphate groups in their backbones. These phosphate groups contain negatively charged oxygen atoms, which make the molecules acidic.
Step 2: Analyzing the options.
- (A) pentose sugar: The pentose sugar does not contribute to the acidity.
- (B) nitrogenous bases: The nitrogenous bases are neutral in terms of acidity.
- (C) phosphate groups: Correct — The phosphate groups in the backbone of DNA and RNA are responsible for their acidic nature.
- (D) large number of hydrogen bonds: Hydrogen bonds do not contribute to the acidic nature of DNA and RNA.
Step 3: Conclusion.
The correct answer is (C) phosphate groups.
| Group I | Group II |
| P) Tissue plasminogen activator | 1) Emergency treatment of heart attack |
| Q) Erythropoietin | 2) Treatment of anemia |
| R) Superoxide dismutase | 3) Prevents tissue damage |
| S) Interferon | 4) Stimulates cells to inhibit viral replication |