Digital SAT Reading and Writing Practice Question #1189

Recent telescopic analyses of exoplanet Trappist-1e have revealed a surprisingly dense atmosphere, with spectroscopic data indicating the presence of significant water vapor and carbon dioxide. While these findings are exciting, the search for biosignatures, such as molecular oxygen (\( \text{O}_2 \)) and methane (\( \text{CH}_4 \)), remains paramount. On Earth, the vast majority of atmospheric oxygen is biogenic, produced by photosynthesis. However, abiotic processes, like the photodissociation of water vapor followed by hydrogen escape, can also generate \( \text{O}_2 \). Therefore, a definitive biological interpretation of exoplanetary oxygen requires careful consideration of co-occurring gases and planetary context to rule out non-biological sources. The passage discusses the challenges in interpreting exoplanetary atmospheric compositions. Which of the following statements *best synthesizes* the textual evidence to support the hypothesis that the detection of atmospheric molecular oxygen (\( \text{O}_2 \)) on an exoplanet is a strong, though not conclusive, indicator of biological activity?