Which of the following is true about the rock shown in the image above?
a.
the rock crystallized from magma deep below the earth's surface.

b.
some of the original materials that formed the rock were made by living organisms.

c.
the rock originally formed in a desert setting.

d.
it is a metamorphic rock that formed from a volcanic rock.

i think it's B.

Explanation:

it looks like shells, which are from clams, and clams are living organisms. i might be wrong, though.

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thinking it would be d not too sure but i think it's right