A small projection from a fungus that penetrates a host to absorb food is a

• A. Haustorium
• B. Hypha
• C. Frass
• D. Habitat

Answer: (A)

A haustorium is a specialized feeding projection that grows from a fungal hypha into a host tissue to absorb nutrients. It forms an intimate interface with the host cells, allowing the fungus to take sugars and other resources while often keeping the host cell alive. This is what enables biotrophic or parasitic fungi to feed efficiently from living hosts.

Hypha refers to the general threadlike filaments that make up most of a fungus, not specifically a penetrating feeding structure. Frass is simply insect excrement, not related to how a fungus absorbs nutrients. Habitat means the environment where an organism lives, not a feeding mechanism.