Digital SAT Reading and Writing Practice Question #751

Recent research into the epigenetic memory of *C. elegans* (a species of nematode) has revealed that environmental stressors, such as starvation, can trigger the production of specific small RNAs. These molecules induce a state of RNA interference (RNAi) that silences certain genes, an adaptation passed down to offspring. Strikingly, scientists observed that this epigenetic memory persists for exactly three generations before being abruptly erased in the fourth generation. However, if a specific gene responsible for the "M-erase" protein is mutated and disabled, the RNAi memory persists indefinitely. Furthermore, introducing a secondary, mild stressor during the third generation resets the biological countdown, allowing the memory to last for an additional three generations. Which statement best describes the logical conclusion that can be drawn from the text?