The correct answer is: marsupials.
Marsupials are actually defined by their ability to hold the young in the pouches, where they can be well protected. Some examples are Kangaroos and Koalas.
Other answers are wrong: for example, gymnosperms are plants, not animals.
Parietal cells produce the acid
Nervous System (brain, spinal cord, nerves)
yes it is correct I would say since in the first place they had to umm... you know... for the female to make fish eggs
