Let the number be 100.

• Correct operation (multiplying by 4): $100 \times 4 = 400$.
• Mistaken operation (dividing by 4): $100 / 4 = 25$.

Now, calculate the difference:

• Difference = $400 - 25 = 375$.

To find the percentage change:

• Percentage change = $(\frac{375}{400}) \times 100 = 93.75\%$.

Answer: D. 93.75%