An atom has mass number 23 and atomic number 11. How many protons, electrons and neutrons are present in the atom?A.11,12,13B.11,11,12C.11,11,13D.11,14,15

To solve the question about the atom with a mass number of 23 and an atomic number of 11, let's first clarify what these terms mean:

1. **Atomic Number (Z)**: This is the number of protons in the nucleus of an atom. It also determines the element's identity. In this case, the atomic number is 11, so the atom has 11 protons.

2. **Mass Number (A)**: This is the total number of protons and neutrons in the nucleus of an atom. For this atom, the mass number is 23.

### Step 1: Determine the Number of Protons
Since the atomic number is 11, the number of protons is:
- **Protons = 11**

### Step 2: Determine the Number of Electrons
In a neutral atom, the number of electrons is equal to the number of protons. Therefore, the number of electrons is:
- **Electrons = 11**

### Step 3: Determine the Number of Neutrons
To find the number of neutrons, we can use the formula:
\[
\text{Neutrons} = \text{Mass Number} - \text{Atomic Number}
\]
Substituting in the values we have:
\[
\text{Neutrons} = 23 - 11 = 12
\]

### Conclusion
Putting it all together, for the atom with mass number 23 and atomic number 11:
- Protons = 11
- Electrons = 11
- Neutrons = 12

So, the correct answer is **B. 11, 11, 12**.