Find out the correct combination.

Options

A. PEP carboxylase `- Mn^(2+)`
B. Cytochrome C-Oxidase - Zinc
C. Nitrate reductase - `Mg^(2+)`
D. Carboxylase - Zinc

Answer

To solve the question "Find out the correct combination," we need to identify which enzyme is activated by which mineral element. Let's analyze each option step by step.

### Step 1: Analyze the First Option
- **Option 1:** Pep carboxylase is activated by manganese.
- **Analysis:** This statement is incorrect. Pep carboxylase is actually activated by magnesium, not manganese.

### Step 2: Analyze the Second Option
- **Option 2:** Cytochrome c oxidase is activated by zinc.
- **Analysis:** This statement is also incorrect. Cytochrome c oxidase is activated by copper, not zinc.

### Step 3: Analyze the Third Option
- **Option 3:** Nitrate reductase is activated by magnesium.
- **Analysis:** This statement is incorrect as well. Nitrate reductase requires molybdenum for its activation, not magnesium.

### Step 4: Analyze the Fourth Option
- **Option 4:** Carboxylase is activated by zinc.
- **Analysis:** This statement is correct. Carboxylase enzymes, such as those involved in the carboxylation reactions, are indeed activated by zinc.

### Conclusion
After analyzing all the options, we find that the correct combination is:
- **Carboxylase is activated by zinc.**

### Final Answer
The correct combination is: **Carboxylase by Zinc.**

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