Consider statements about microorganisms: 1. Bacteria can be autotrophic or heterotrophic. 2. Viruses are considered living outside a host. 3. Fungi are eukaryotic organisms. Which are correct? MCQ with Answer and Explanation

Bacteria exhibit diverse nutritional modes; some are autotrophic (photosynthetic like cyanobacteria or chemosynthetic), while others are heterotrophic (saprophytic or parasitic). Fungi are eukaryotic organisms, characterized by having a true nucleus and membrane-bound organelles, and are heterotrophic. Viruses are considered non-living outside a host cell because they lack metabolic machinery and cannot replicate independently; they only exhibit living characteristics inside a host. Thus, statements 1 and 3 are correct.