Answer:
The waste products are Carbon Dioxide and Water.
Explanation:

Carbon dioxide in the tissues is produced as the result of oxidation of glucose...
This carbon dioxide in process of respiration diffuse out of the tissues in form of molecular carbon dioxide and join with water forming carbonic acid ...
In lungs again carbon dioxide is separated and released out of the body...
Answer:
The answer is:
E. They lack a plasma membrane.
The reason is that the plasma membrane is actually a very important part of their cell. Hope that helps! :)