Final answer:
Ridge push increases slab pull by exerting force on the slab.
Step-by-step explanation:
The correct statement that describes how ridge push can affect slab pull is:
The lithosphere at an oceanic ridge is pulled down by gravity and exerts force on the slab, increasing slab pull.
Ridge push and slab pull are two forces that contribute to plate motion. Ridge push occurs at oceanic ridges where new crust is formed. The force of gravity pulls the denser lithosphere down at the ridge, creating a pushing force that drives plate motion. Slab pull, on the other hand, is the force exerted by a subducting plate as it sinks into the mantle.
Therefore, ridge push increases slab pull because the downward force exerted by the lithosphere at the ridge adds to the overall pulling force of the subducting plate.
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