Which kingdom obtains food by ingesting and digesting other organisms, classifying them as heterotrophs?

• A. Heterotrophs
• B. Autotrophs
• C. Detritivores
• D. Protists

Answer: (A)

Heterotrophy is the feeding mode where organisms obtain energy and carbon by ingesting and digesting other organisms. This means they rely on preformed organic molecules from others rather than making their own food. So, describing a kingdom by its nutrition—consuming and breaking down living or dead organisms—best fits the term heterotrophs. Autotrophs, by contrast, make their own organic matter through photosynthesis or chemosynthesis. Detritivores refer to a feeding habit (consuming detritus) rather than a broad kingdom-level classification. Protists is a diverse group with many different nutrition strategies, including both autotrophy and heterotrophy, so it doesn’t specify the feeding mode as clearly.