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Some organisms adapt to periodic harsh conditions by building a resistant stage, or diapause, into their life cycle. A. The diapause stage evolved very early and is most common in species that first appeared more than 10,000 years ago. B. Unpredictable conditions are more problematic for organisms than are fairly predictable changes such as the seasons. C. Some seeds may germinate in three days even if they have been exposed to very low temperatures for a long time. D. Some marsupials can care for three newborns in their pouch at the same time, allowing the young to leave the pouch only when conditions are favorable for their growth. E. The female red kangaroo adapts to unfavorable conditions by delaying the development of the embryo in the uterus. F. Some amphibians adapt to arid environments by completing accelerated development with resting stages deep underground.