Nucleotides include:

Options

A. ATP
B. coenzyme subunits
C. DNA and RNA subunits
D. all of the above

Explanation

To determine what nucleotides include, we will analyze the options provided in the question step by step.

### Step 1: Understand the structure of nucleotides
Nucleotides are the basic building blocks of nucleic acids (DNA and RNA). Each nucleotide consists of three main components:
1. **Pentose Sugar**: This can be ribose (in RNA) or deoxyribose (in DNA).
2. **Nitrogenous Base**: There are two categories of nitrogenous bases:
- **Purines**: Adenine (A) and Guanine (G).
- **Pyrimidines**: Cytosine (C), Thymine (T) in DNA, and Uracil (U) in RNA.
3. **Phosphate Group**: This is attached to the sugar molecule.

### Step 2: Analyze the options
Now, let's evaluate the options given in the question:

1. **CTP**: This is a nucleotide (cytidine triphosphate) and thus a valid example of a nucleotide.
2. **Coenzyme subunits**: Coenzymes are not nucleotides; they are organic non-protein molecules that assist enzymes.
3. **DNA and RNA subunits**: Nucleotides are indeed the subunits that make up DNA and RNA.
4. **All of the above**: This would only be correct if all previous options were correct.

### Step 3: Conclusion
From the analysis:
- CTP is a nucleotide.
- Coenzyme subunits are not nucleotides.
- DNA and RNA subunits are made of nucleotides.

Thus, the correct answer is **DNA and RNA subunits**.

### Final Answer:
Nucleotides include DNA and RNA subunits.

---