which of the following is most likely to be an observation made by an anatomist? select one: a. rna polymerase binds to a promoter, a dna sequence that becomes a gene. b. sensory receptors convert information into impulses to be sent to the cns. c. the heart's epicardium forms a protective outer covering and secretes serous fluid. d. the middle ear is an air-filled space that separates the outer and inner ear.