Correct Response: D. Deep-ocean currents are part of the ocean's thermohaline circulation, which is driven by temperature and salinity gradients in the oceans. Deep-ocean currents are not affected by surface wave energy (A) as the energy of surface waves dissipates rapidly with depth. The Moon's gravitational pull is a major driver of ocean tide cycles, but it does not have a significant effect on deep- ocean currents (B). Although Earth's orbital and rotational motion affects ocean circulation (C), it is not a primary driver of the thermohaline circulation that produces deep-ocean currents.
