Lichens multiply by

Options

A. conidia
B. oidia
C. ascospores
D. soredia

Answer

**Step-by-Step Solution:**

1. **Understanding Lichens**: Lichens are symbiotic associations between fungi and algae or cyanobacteria. They can reproduce both sexually and asexually.

2. **Types of Reproduction**: While lichens can reproduce sexually through the formation of spores, they primarily reproduce asexually. This is important to note as the question specifically asks about the method of multiplication.

3. **Asexual Reproduction in Lichens**: The most common method of asexual reproduction in lichens is through vegetative means. This involves the formation of specialized structures.

4. **Identifying the Correct Structure**: Among the options given (conidia, oidia, ascospores, and suridia), we need to identify which one is associated with the vegetative reproduction of lichens.

5. **Suredia Formation**: Suredia are small, dust-like structures that can be produced on the thallus (the body of the lichen). They consist of a few algal cells surrounded by fungal cells and are crucial for the dispersal of lichens.

6. **Conclusion**: Based on the above information, the correct answer to the question "Lichens multiply by" is **option D: Suredia**.

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