Question

lightning round: word jumble dmi- oneca gider hint: it forms under the ocean where plates are spreading apart. check answer

Explanation:

The hint indicates a geological feature formed at ocean - spreading centers. Rearranging the jumbled letters "DMI - ONECA GIDER" gives "MID - OCEAN RIDGE", which is a long, seismically active submarine mountain system formed by plate tectonics as plates spread apart.

Answer:

MID - OCEAN RIDGE