In which type of ecosystem would you find a cactus?

The correct answer is the desert ecosystem, where cacti thrive due to specific environmental conditions. Desert ecosystems are characterized by low rainfall, high temperatures, and a lot of sunlight, which are ideal for the survival of cacti. These plants have adapted to conserve water through various mechanisms, such as thick, fleshy tissues that store moisture, a waxy coating on their surfaces to reduce water loss, and photosynthesis occurring in their stems instead of leaves to minimize surface area exposed to the sun.

In contrast, tropical rainforests receive abundant rainfall and support a different range of plant species that require a moist and humid environment. Grasslands, while potentially having some drought-resistant plants, do not typically support cacti as their primary vegetation due to the presence of grasses being dominant. Temperate forests provide a cooler, wetter climate that is unsuitable for cacti, which are specialized for arid conditions. Thus, the desert is the only ecosystem among the options that supports the growth and survival of cacti effectively.