Answer:
Classification system changes because the scientists find new evidence in their studies.
Explanation: The world is always changing and growing and dying as well as developing, so over time things change. For example, as you grow up do you stay the same? No, you notice the physical changes happening, well thats sort of like how the earth and its ways are always changing as well.
The key evolutionary development of animals seen for the first time in sponges is that of Multicellularity. A Multicellular organism has a longer lifespan than an unicellular organism and since it has multiple cells, it can perform more functions. Sponges do not have distinct circulatory, respiratory, digestive, and excretory systems – instead the water flow system supports all these functions.
Answer:
C.
Explanation:
Because for answer A, only eukaryotes have DNA, also for B, only eukaryotes have a nucleus and lastly, for D, only eukaryotes contain membrane-bound organelles. hope this helps :)