For which of the following elements, the symbol consists of only one letter?

Options

A. Calcium
B. Chlorine
C. Carbon
D. Copper

Answer

To determine which of the given elements has a symbol that consists of only one letter, we will analyze each element's symbol and atomic number. Here are the steps:

### Step 1: List the Elements and Their Symbols
We will start by listing the elements provided in the question along with their symbols and atomic numbers.

1. **Calcium (Ca)**
- Symbol: Ca
- Atomic Number: 20

2. **Chlorine (Cl)**
- Symbol: Cl
- Atomic Number: 17

3. **Carbon (C)**
- Symbol: C
- Atomic Number: 6

4. **Copper (Cu)**
- Symbol: Cu
- Atomic Number: 29

### Step 2: Identify Symbols with One Letter
Next, we will check each symbol to see if it consists of only one letter.

- **Calcium (Ca)**: The symbol has 2 letters (C and a).
- **Chlorine (Cl)**: The symbol has 2 letters (C and l).
- **Carbon (C)**: The symbol has 1 letter (C).
- **Copper (Cu)**: The symbol has 2 letters (C and u).

### Step 3: Conclusion
From the analysis, we can see that only **Carbon (C)** has a symbol that consists of only one letter.

### Final Answer
The element whose symbol consists of only one letter is **Carbon**.

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