Which of the following is radioactive element

Options

A. Sulphur
B. Polonium
C. Tellurium
D. Selenium

Answer

To determine which of the given elements is radioactive, we can follow these steps:

### Step 1: Identify the Elements and Their Atomic Numbers
We need to identify the atomic numbers of the given elements. The elements mentioned in the question are:
- Sulfur (S)
- Selenium (Se)
- Tellurium (Te)
- Polonium (Po)

### Step 2: Look Up Atomic Numbers
Now, let's look up the atomic numbers for these elements:
- Sulfur (S) has an atomic number of 16.
- Selenium (Se) has an atomic number of 34.
- Tellurium (Te) has an atomic number of 52.
- Polonium (Po) has an atomic number of 84.

### Step 3: Determine Radioactivity
According to the information provided, elements with atomic numbers greater than or equal to 82 are considered radioactive.

### Step 4: Analyze the Atomic Numbers
- Sulfur (16) - Not radioactive
- Selenium (34) - Not radioactive
- Tellurium (52) - Not radioactive
- Polonium (84) - Radioactive

### Step 5: Conclusion
Since Polonium (Po) is the only element among the options with an atomic number greater than 82, it is the only radioactive element listed.

Thus, the correct answer is **Polonium (Po)**.

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