No species lasts forever. Our species has been in existence for at least 200,000 years and is not old in evolutionary terms. Consequently, we should persist for hundreds of thousands of years yet there are no indications that Homo sapiens is in decline. However, whether we have the capacity for total destruction — through nuclear annihilation or such — remains debated. Some experts argue that humans are so numerous, widespread and suited to survive catastrophe that no event would result in extinction. A collapse of global ecosystems resulting from climate change and overpopulation has also been predicted as a cause for our extinction but, again, it is difficult to accept that such events could cause human die-off everywhere. Ultimately, it is impossible to predict what might happen in coming centuries. But, more so than any other species, humanity is able to control its evolution via the use of technology, genetic modification and the control of resources; these factors make it likely that we will persist for longer than has been typical for mammal species before us.
Why would global ecosystems collapse?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Climate change and overpopulation.
The passage speaks of "a collapse of global ecosystems resulting from climate change and overpopulation". These two are named as the causes of the collapse.
Why the Other Options are Incorrect?
Option 1: Use of technology and genetic modification — Incorrect. Wrong link: these are the means by which humanity is able to control its evolution and survive longer, not causes of collapse.
Option 2: Nuclear Annihilation — Incorrect. Wrong link: annihilation means complete destruction. The passage mentions it as a separate, debated way in which humans might destroy themselves, not as a cause of ecosystem collapse.
Option 4: Because of human die-off everywhere — Incorrect. Result, not cause: a human die-off everywhere is the possible outcome of the collapse, and the passage even doubts it.