Simplify the expression. Write your answer with positive exponents only. \[ \frac{18^{12}}{18^{5}} \] Select one: a. $18^{12}-18^{5}$ b. $18^{7}$ C. $18^{12 / 5}$ d. $18^{17}$

Step 1 ：The problem is asking to simplify the expression \(\frac{18^{12}}{18^{5}}\).

Step 2 ：This is a basic exponent rule where when you divide two numbers with the same base, you subtract the exponents.

Step 3 ：So, the simplified expression would be \(18^{12-5}\).

Step 4 ：Subtracting the exponents gives us \(18^{7}\).

Step 5 ：Calculating \(18^{7}\) gives us 612220032.

Step 6 ：\(\boxed{612220032}\) is the final answer.