To determine which of the given options consists entirely of nucleotides, we first need to understand what a nucleotide is. A nucleotide is a compound made up of three components:
1. A nitrogenous base (which can be adenine, guanine, cytosine, thymine, or uracil).
2. A sugar molecule (either ribose in RNA or deoxyribose in DNA).
3. One or more phosphate groups.
Now, let's analyze each option provided in the question:
1. **Option 1: Adenosine, Cytidilic Acid, and Cytosine**
- Adenosine is a nucleoside (it consists of adenine and ribose).
- Cytidilic acid is a nucleotide (it consists of cytosine, ribose, and phosphate).
- Cytosine is a nitrogenous base, not a nucleotide.
- **Conclusion**: This option is incorrect because it contains a nucleoside and a nitrogenous base.
2. **Option 2: Adenalic Acid, Cytidilic Acid, and Guanalic Acid**
- Adenalic acid (also known as adenylic acid) is a nucleotide (adenine + ribose + phosphate).
- Cytidilic acid is a nucleotide (cytosine + ribose + phosphate).
- Guanalic acid (also known as guanylic acid) is a nucleotide (guanine + ribose + phosphate).
- **Conclusion**: This option is correct because all components are nucleotides.
3. **Option 3: Cytidine, Adenine, Adenalic Acid, Uracil, Thymidine, and Thymidilic Acid**
- Cytidine is a nucleoside (cytosine + ribose).
- Adenine is a nitrogenous base, not a nucleotide.
- Adenalic acid is a nucleotide.
- Uracil is a nitrogenous base, not a nucleotide.
- Thymidine is a nucleoside (thymine + ribose).
- Thymidilic acid is a nucleotide.
- **Conclusion**: This option is incorrect because it contains nucleosides and nitrogenous bases.
4. **Option 4: Uracil, Thymidine, and Thymidilic Acid**
- Uracil is a nitrogenous base, not a nucleotide.
- Thymidine is a nucleoside (thymine + ribose).
- Thymidilic acid is a nucleotide.
- **Conclusion**: This option is incorrect because it contains a nitrogenous base and a nucleoside.
Based on the analysis, the only option that contains all nucleotides is **Option 2: Adenalic Acid, Cytidilic Acid, and Guanalic Acid**.
### Summary of the Solution:
- Identify what constitutes a nucleotide.
- Analyze each option for the presence of nucleotides.
- Conclude that Option 2 is the only one with all nucleotides.
