Given that each story of the office building is 9 3/4 feet in height and the building has three underground levels, we need to determine the elevation of a car parked two levels below ground.

First, let's convert 9 3/4 feet to an improper fraction for easier calculations: $9 \frac{3}{4} = \frac{9 \times 4 + 3}{4} = \frac{36 + 3}{4} = \frac{39}{4} \text{ feet}$

Since the car is parked two levels below ground, we need to find the height of these two levels combined: $2 \times \frac{39}{4} = \frac{78}{4} = 19 \frac{1}{2} \text{ feet}$

Since the car is parked below ground, the elevation relative to the ground level (which is 0 feet) will be negative: $-19 \frac{1}{2} \text{ feet}$

So, the correct answer is: $A. -19 \frac{1}{2} \text{ feet}$

Would you like further details or have any questions?

Here are 5 questions you might ask next:

1. How do you convert mixed numbers to improper fractions?
2. How do you multiply fractions?
3. How do you convert an improper fraction back to a mixed number?
4. What are some common mistakes to avoid when working with negative elevations?
5. How do you calculate the total height for multiple levels?

Tip: Always double-check your calculations to ensure accuracy, especially when working with fractions and negative numbers.