So,
[tex] \sqrt{75} - 4 \sqrt{8} - 3 \sqrt{32} [/tex]
Simplify the radicals.
[tex] \sqrt{25} * \sqrt{3} - 4 * \sqrt{4} * \sqrt{2} - 3 * \sqrt{16} * \sqrt{2} [/tex]
[tex]5 * \sqrt{3} - 4 * 2 * \sqrt{2} - 3 * 4 * \sqrt{2} [/tex]
[tex]5\sqrt{3} - 8 * \sqrt{2} - 12 * \sqrt{2} [/tex]
[tex]5\sqrt{3} - 8\sqrt{2} - 12\sqrt{2} [/tex]
[tex]5\sqrt{3} - 20\sqrt{2}[/tex]
The correct answer is C.