Which kingdom includes organisms that perform photosynthesis?

Organisms that perform photosynthesis primarily belong to the kingdom of Plants. In this kingdom, plants convert solar energy into chemical energy through the process of photosynthesis, using chlorophyll found in their chloroplasts. This ability enables them to synthesize their own food from carbon dioxide and water, releasing oxygen as a byproduct. This characteristic is fundamental to the role of plants in ecosystems as primary producers, forming the base of the food chain.

While other kingdoms, such as Protists, may include some photosynthetic organisms (like algae), the majority of organisms known for this ability are categorized within the Plant kingdom. Therefore, choosing Plants as the answer accurately reflects the dominant group responsible for photosynthesis in nature.