Question

select the scientific process skill(s) which helped robert hooke discover plant cells in the tissue of a cork oak tree. communicating observing experimenting questioning

Explanation:

Robert Hooke used a microscope to look at the cork - oak tissue. This is an act of observing. He did not communicate to discover the cells, did not conduct experiments to find them initially, and questioning was not the main skill in the act of discovery.

Answer:

observing