Bus: Driver :: ?:?

Options

A. Cook : Kitchen
B. Class : Student
C. War: Soldier
D. Machine : Operator

Explanation

To solve the analogy "Bus: Driver :: ?:?", we need to find a pair of words that have a similar relationship to that of "Bus" and "Driver."

### Step-by-Step Solution:

1. **Understand the Relationship**:
- A bus requires a driver to operate. The driver is essential for the bus to function properly.

2. **Analyze the Options**:
- We have four options to consider. We need to check which option has a similar relationship where the first word requires the second word for its operation.

3. **Evaluate Option 1: Cook and Kitchen**:
- A kitchen is a place where a cook works. However, a cook does not need a kitchen to exist; they can cook elsewhere. Thus, this option does not follow the same relationship as Bus and Driver.

4. **Evaluate Option 2: Class and Student**:
- A class is a space where students learn, but a class does not require students to exist. Therefore, this option also does not fit the relationship.

5. **Evaluate Option 3: War and Soldier**:
- A war involves soldiers, but a war does not need soldiers to exist; it can be declared without them. Hence, this option does not match the relationship.

6. **Evaluate Option 4: Machine and Operator**:
- A machine requires an operator to function. Just like a bus needs a driver, a machine needs an operator to perform its tasks. This option closely mirrors the relationship of Bus and Driver.

7. **Conclusion**:
- The correct answer is Option 4: Machine and Operator, as it maintains the same relationship where the first word (Machine) requires the second word (Operator) for its operation.

### Final Answer:
**Machine: Operator**

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