Question

this diagram shows fossils in an undisturbed sedimentary rock sequence.
shallower
deeper
which of the following fossils is oldest? select the most likely answer.
fish
clam
worm burrow

Explanation:

In undisturbed sedimentary rock layers, the principle of superposition states that older layers are deeper (formed earlier) and younger layers are shallower (formed later). The clam fossil is in the deepest layer of the rock sequence, so it is the oldest among the given fossils.

Answer:

B. clam