Read the following statements and choose the follwoing option: 1. Eubacteria are characterised by the presence of cell membrane 2. Cyanobacteria are photosynthetic autotrophs 3. Cyanobacteria are filamentous, unicellular algae 4. Heterotrophic bacteria are not abundant in nature.

Step-by-step solution

The cyanobacteria (also referred to as blue-green algae) have chlorophyll a similar to green plants and are photosynthetic autotrophs. The cyanobacteria are unicellular, colonial or filamentous, freshwater/marine or terrestrial algae. The colonies are generally surrounded by gelatinous sheath.