Sand dollars, clams, and sand crabs usually live in
a. salt marches.
b. tide pools.
c. rocky shores.
d. sandy shores.

Option D, sandy shores

Explanation:

On a sandy beach, the movement of sand does not allow the survival of large plants and animals .  Thus, plants like seaweeds, visitor animals or small organisms which are able to live beneath sandy  soil of beach  survive in a moving landscape. Sand dollars, clams, and sand crabs live in the submerged beach section of a marine beach.  They all feed on plankton and small organic particles found on the sand . They remain half buried during normal sea wave  while during stormy condition they dig deep into the sea shore.

Hence, option D is the right choice of answer

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