The Kuril–Kamchatka Trench (to give it its full name) is the fourth–deepest of the world's ocean trenches – after the Mariana, Tonga and Philippine trenches.
Wikipedia lists 23 "notable oceanic trenches" – 22 of which are in the Pacific Ocean. The exception is the Puerto Rico Trench, which is the eighth deepest.
(This is a polite way of saying that this is really just a non–question.)
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