`{:("Quantity A","Quantity B"),("The product of 12 and an even","The sum of the greatest four"),("prime number","factors of 12"):}`

Answer

To solve the problem, we need to evaluate both Quantity A and Quantity B step by step.

### Step 1: Calculate Quantity A
**Quantity A** is defined as the product of 12 and an even prime number.

The only even prime number is **2**.

So, we calculate:
\[ \text{Quantity A} = 12 \times 2 = 24 \]

### Step 2: Calculate Quantity B
**Quantity B** is defined as the sum of the greatest four factors of 12.

First, we need to identify the factors of 12. The factors of 12 are:
1, 2, 3, 4, 6, and 12.

Now, we need to find the greatest four factors of 12:
- The greatest four factors are: **12, 6, 4, and 3**.

Now, we calculate the sum of these four factors:
\[ \text{Quantity B} = 12 + 6 + 4 + 3 \]
Calculating this step-by-step:
- \(12 + 6 = 18\)
- \(18 + 4 = 22\)
- \(22 + 3 = 25\)

So, we have:
\[ \text{Quantity B} = 25 \]

### Step 3: Compare Quantity A and Quantity B
Now we compare the two quantities:
- Quantity A = 24
- Quantity B = 25

Since \(25 > 24\), we conclude that:
\[ \text{Quantity B is greater than Quantity A.} \]

### Final Conclusion
Thus, the answer is that Quantity B is greater than Quantity A.

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