Which of these oceanic landforms is similar to a canyon?
a) valley
b) seamount
c) ocean trench
d) the mid-ocean ridge

Option (C)

Explanation:

The oceanic trenches are often defined as those long and narrow type of depressions that are formed at the seafloor, along a convergent plate boundary between two oceanic plates or continental and an oceanic plate.

Canyons are the erosional features that are formed due to the down-cutting of the surface rocks by a deep and narrow type of river channel, giving rise to the formation of steep cliffs on both the sides of the channel.

Both these features are similar in appearance but oceanic trenches are formed at the bottom of the ocean whereas canyons are formed at the surface of the earth.

Thus, the correct answer is option (C).