The outer skeleton provides protection due to the fact that invertebrates do not have backbones
Answer:
the answer is d. Hope this helps
There are two main types of research, which could be classified as manipulation and observation. Both types are fundamental in research.
<h3>Empirical research and evolution</h3>
Evolution is the subdiscipline in biology that studies how organisms change to adapt to challenging environmental conditions.
Empirical research refers to any scientific investigation in which conclusions are drawn from empirical evidence.
This type of research (empirical research) is based on observation of the natural world and experimental procedures.
Learn more about empirical research here:
brainly.com/question/6862874
All cells have DNA, cytoplasm, and ribosomes