Read the passage. The conclusion that pumping rhythm reflected feeding opportunity and light-driven internal changes is stated before the narrative of the investigation is complete. The narrative later identifies the first evidence: sponges pumped more water at night than during bright afternoons. That evidence led to a hypothesis that night pumping helped them feed when plankton were abundant. A test followed, carried out by measuring sponge flow while manipulating plankton levels and light conditions. The test required a revision to say that bright light caused symbiotic microbes to alter sponge canal pressure. Which choice orders the investigation from earliest step to final claim?