The answer is c because they are not identical to parents but have some things in common ( resemble)
Answer:
Parasitism
ExplanatioThe flatworm seems to be the only one benefitting from the relationship because it is using the snail as a host and provides it a place to grow but the snail is being harmed by the worm while doing so. Therefore the relationship is parasitic.
What chart-
more context needed edit question
B, both chemical and biological factors are involved