What adaptations do cacti have to survive in arid environments?

Cacti have evolved several remarkable adaptations that allow them to thrive in arid environments where water is scarce. The characteristics that make option B the correct choice include thick stems, which serve a vital purpose; they are designed to store water during the infrequent rainfalls that occur in desert regions. This adaptation is crucial for survival as it enables the cactus to access moisture when it is not readily available.

Another significant adaptation in cacti is the presence of spines instead of leaves. This modification reduces surface area, thereby minimizing water loss through transpiration, which is essential in a hot, dry climate. The spines also serve as a defense mechanism against herbivores, reducing the chances of being eaten by animals seeking moisture-rich plants. Furthermore, cacti contain specialized water storage tissues that allow them to retain moisture more effectively.

The other choices present adaptations that are not suited for survival in arid conditions. For example, large leaves and shallow roots would increase water loss and be inefficient in seeking out moisture in deep soils. Bright flowers, while they can attract pollinators, do not aid in water retention, and deep roots without the other adaptations would not sufficiently support survival in such harsh environments. Thin stems and extensive leaf cover would also contribute to greater water