Final answer:
Ocean sediment is thinnest near Mid-Ocean Ridges and thickest closer to continents, making the statement false.
Step-by-step explanation:
The statement 'Is ocean sediment thickest proximal to MOR? is false. Ocean sediment is typically thinnest near the Mid-Ocean Ridges (MOR) because this is where new oceanic crust is formed.
Sediments are carried to the ocean primarily from land via rivers and wind currents, hence sediment is generally thickest closer to the continents. As you move away from the MOR, toward continents, the age of the seafloor increases and the thickness of the sediment accumulates over time.