Define the plate tectonics?​

Plate tectonics is a scientific theory describing the large-scale motion of the plates making up Earth's lithosphere since tectonic processes began on Earth between 3.3 and 3.5 billion years ago. The model builds on the concept of continental drift, an idea developed during the first decades of the 20th century.

a theory explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates which move slowly over the underlying mantle.

Explanation:

the answer to your question is,

d. when a child was born.

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