It looks like you're asking to simplify the expression $5\sqrt{3}\sqrt{6}$.

Let's break it down:

1. When you have two square roots multiplied together, you can combine them into one square root:

$5\sqrt{3} \cdot \sqrt{6} = 5\sqrt{3 \times 6} = 5\sqrt{18}$

2. Next, simplify $\sqrt{18}$. Since $18 = 9 \times 2$, and $\sqrt{9} = 3$, we have:

$\sqrt{18} = \sqrt{9 \times 2} = 3\sqrt{2}$

3. Therefore, the entire expression becomes:

$5\sqrt{3} \cdot \sqrt{6} = 5 \times 3\sqrt{2} = 15\sqrt{2}$

Thus, the simplified form of $5\sqrt{3} \cdot \sqrt{6}$ is:

$\boxed{15\sqrt{2}}$

It appears that none of the options perfectly match this form. If the expression you gave is correct, the answer should be $15\sqrt{2}$, which is not listed in your options.

Would you like further clarification or help with another problem?

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Here are some related questions to help expand on this topic:

1. How do you simplify expressions with multiple square roots?
2. What other rules apply to simplifying radical expressions?
3. Can you simplify $\sqrt{a} \cdot \sqrt{b}$ with different types of radicals?
4. What if the original expression had cube roots? How would that change the process?
5. What happens when you have a cube root of a product like $\sqrt[3]{6 \cdot 4}$?

Tip: Always try to simplify radicals by factoring numbers inside the square root to look for perfect squares or cubes.