When Dr. Philip tierno conducted his experiment on the pillows , he wanted to know the connection between pillows and the allergy-causing germs. He was trying to answer the question, Do these pillows contain germs that contribute to the family allergies?

Yes. That was the question he was trying to answer.

Explanation:

To conduct the experiment investigating the connection between pillows and disease-causing gems, Dr. Philip needs to ask himself whether the pillows that will be used in the research contain germs that contribute to allergies in a family. This question allows Dr. Philip to have the basis to start his research and come to a conclusion about the pillows used in the research. Furthermore, the research points directly to the main point of the story.

a bird that nests only in a particular tree species.