A cave, from the water slowly cracking and chipping away at the rock it seeps down into, creating freshwater, but also, slowly creating a cave.
The correct answers are:
Trematodes are acoelomates that have effective defenses against attack by their hosts' immune system.
Trematodes are flatworms, internal parasites known as flukes. Their life cycle is complex: they sexually reproduce in vertebrates and asexual reproduce in mollusks (mostly snail). The body of flukes is covered with tough tegument that defends them form digestive enzymes of host’s intestine.
Cnidarians are diploblasts that produce complex, capsule-like organelles.
Cnidaria are water organisms with simple structure: two layers of epithelium and a jelly substance between them. The cells of Cnidaria-cnidocytes contain capsule with venom substance in it with protective role.
The only logical answer would be C. Unicellular, but the answers seem to be all wrong.
D. <span>controlled
is the right answer because a</span><span>n </span>experiment<span> in which an observer tests a hypothesis by looking for changes carried by alterations to a variable.</span>
I'm sure it's true since before doing a science experiment/If you're trying to figure something out, you need a Hypothesis.