Most algal genera show haplontic life style. Name an alga which is (a) Haplo diplontic (b) Diplontic

Explanation

To solve the question regarding algal life cycles, we will break it down into two parts: identifying an alga that exhibits a haplo-diplontic lifestyle and one that shows a diplontic lifestyle.

### Step-by-Step Solution:

1. **Understanding Algal Life Cycles**:
- Algae can exhibit different life cycles: haplontic, haplo-diplontic, and diplontic.
- In a **haplontic** life cycle, the main plant body is haploid (n), and the diploid (2n) phase is usually short-lived.
- In a **haplo-diplontic** life cycle, both haploid (gametophyte) and diploid (sporophyte) phases are present and alternate.
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