Since the early 1990s, proton pump inhibitors (PPIs) have been widely used to treat acid reflux disease. Although clinical tests in the 1980s deemed PPIs to be safe for humans, in 2012 the FDA announced warnings that long-term use of PPIs could increase the risk of bone fractures, kidney disease, and some intestinal infections. Which statement best explains why the safety of PPIs is now in question when clinical experiments in the 1980s provided evidence that they were safe?

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).

enhanced global partnerships and exploration capabilities may advance international preparedness for protecting the earth from catastrophic events such as some asteroid strikes, advancing collaborative research on space weather and protecting spacecraft by developing new means for space debris removal.