Multiple Choice
Modern sponges produce spicules to deter predation,but as the earliest animals,they existed before any predators evolved; which of the following hypotheses regarding the formation of spicules is the least likely?
A) Spicules were probably absent in the earliest sponges and evolved later as predation began.
B) Spicules performed other tasks in early sponges, possibly structural support, and were later modified for defense.
C) Spicules were present in some sponge species and absent in others; predation became a selection pressure that eliminated some species entirely.
D) Much like the acquisition of cnidocytes by nudibranchs, some sponges incorporated the spicules they consume into their bodies rather than digesting them.
Correct Answer:

Verified
Correct Answer:
Verified
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