Which of the following pairs of organisms are correctly matched with their description ?
1. Pteridophytes which are heterosporous : Selaginella , salvinia
2. Gymnosperms with branched stem : Pinus , Cedrus
3. Algae with haplo - diplontic life cycle : Ectocarpus, polysiphonia
4. Bryophytes with protonema stage : polytrichum , sphagnum

Options

A. 1, 3
B. 2, 4
C. 1,2,3,4
D. 1,3,4

Answer

To determine which pairs of organisms are correctly matched with their descriptions, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Pteridophytes which are heterosporous: Selaginella, Salvinia**
- Pteridophytes are vascular plants that can be either homosporous (producing one type of spore) or heterosporous (producing two different types of spores).
- Selaginella and Salvinia are both examples of heterosporous pteridophytes.
- **Conclusion**: This pair is correctly matched.

2. **Gymnosperms with branched stem: Pinus, Cedrus**
- Gymnosperms are seed-producing plants that do not form flowers or fruits.
- Pinus (pine) and Cedrus (cedar) are both examples of gymnosperms.
- While Pinus typically has a branched stem, Cedrus also has a branched structure.
- **Conclusion**: This pair is correctly matched.

3. **Algae with haplo-diplontic life cycle: Ectocarpus, Polysiphonia**
- The haplo-diplontic life cycle involves both haploid and diploid stages.
- Ectocarpus (a brown alga) and Polysiphonia (a red alga) both exhibit this life cycle.
- **Conclusion**: This pair is correctly matched.

4. **Bryophytes with protonema stage: Polytrichum, Sphagnum**
- Bryophytes are non-vascular plants that include mosses and liverworts.
- The protonema is an early stage in the life cycle of mosses, which develops from spores.
- Polytrichum and Sphagnum are both examples of mosses that have a protonema stage.
- **Conclusion**: This pair is correctly matched.

### Final Answer:
All four pairs are correctly matched with their descriptions.