Which of the following group represents all beneficial elements ?

Options

A. Na, Si, Se, Ag
B. Na, Se, Cu, Co
C. Na, Si, Co, Se
D. Na, Ne, Se, Co

Answer

To solve the question of which group represents all beneficial elements, we will analyze each option given in the question step by step.

### Step 1: Understand Beneficial Elements
Beneficial elements are minerals that are essential for the growth and normal functioning of plants. The known beneficial elements include sodium, silicon, cobalt, and selenium.

### Step 2: Analyze Each Option
1. **Option 1: Sodium, Silicon, Selenium, Silver**
- Sodium: Beneficial
- Silicon: Beneficial
- Selenium: Beneficial
- Silver: Not beneficial
- **Conclusion**: This option is incorrect because it includes silver, which is not a beneficial element.

2. **Option 2: Sodium, Selenium, Copper, Cobalt**
- Sodium: Beneficial
- Selenium: Beneficial
- Copper: Not beneficial
- Cobalt: Beneficial
- **Conclusion**: This option is incorrect because it includes copper, which is not a beneficial element.

3. **Option 3: Sodium, Selenium, Cobalt, Silicon**
- Sodium: Beneficial
- Selenium: Beneficial
- Cobalt: Beneficial
- Silicon: Beneficial
- **Conclusion**: This option is correct as all listed elements are beneficial.

4. **Option 4: Sodium, Neon, Selenium, Cobalt**
- Sodium: Beneficial
- Neon: Not beneficial
- Selenium: Beneficial
- Cobalt: Beneficial
- **Conclusion**: This option is incorrect because it includes neon, which is not a beneficial element.

### Step 3: Final Conclusion
After analyzing all the options, we find that **Option 3: Sodium, Selenium, Cobalt, Silicon** is the only group that represents all beneficial elements.