The rhetoric mentioned in line 6 refers to the idea that authentic science depended upon actual experiments performed by the scientists themselves (lines 8-10), meaning the rhetoric would suggest that Boyle himself actually performed all of the thousand-plus experiments (lines 20-24). The author tells us that in contrast to this rhetoric, most of the labor of recording and obtaining results is properly attributed to paid technicians (lines 25-27). The question asks us which of the following descriptions of experimentation in Boyle's laboratory would be consistent with the aforementioned rhetoric. The rhetoric required that all experiments were performed by the scientist himself, hence (E) is the correct answer.