Question

multiple-choice question
what does a layer of limestone in sedimentary rock tell us?
a. the area was once covered by water, like a prehistoric swimming pool.
b. dinosaurs had a secret underwater city here.
c. ancient mermaids used this place as a spa.
d. a giant clam exploded, leaving behind its remains.

Explanation:

Limestone is a sedimentary rock formed mainly from the accumulation of marine organism remains and chemical precipitation in aquatic environments. This means the area where limestone formed was once under water. The other options are fictional or scientifically invalid.

Answer:

A. The area was once covered by water, like a prehistoric swimming pool.