Final Answer:
Plants that are efficient at using resources in stress environments and have adaptations for temperature and water regulation are known as xerophytes.
Step-by-step explanation:
Xerophytes are plants adapted to thrive in stress environments characterized by limited water availability and fluctuating temperatures. These plants have evolved various mechanisms to efficiently use resources and survive in arid or semi-arid conditions. Common adaptations include reduced leaf surface area, deep root systems to access water, and mechanisms for water retention, such as succulence or waxy coatings. Xerophytes have developed these traits to cope with the challenges of stress environments, allowing them to conserve water and maintain physiological functions in conditions where water availability is a limiting factor.