Which of the following is a wrong combination?

Options

A. (a) Haploid endosperm, archegonia present but antheridium absent - Gymnosperms
B. (b) Triploid endosperm and 7-celled female gametophyte called embryo sac - Angiosperms
C. (c) Embryo stage absent, reproduction by spores - Algae
D. (d) Gametophyte independent, biflagellate gametes and reproduction by accessory spores - Mosses.

Answer

To determine which of the following combinations is incorrect, we will analyze each option step by step.

### Step 1: Analyze Gymnosperms
- **Characteristics**:
- **Haploid Endosperm**: Gymnosperms have a haploid endosperm, which is essentially the female gametophyte.
- **Archegonia Present**: Archegonia, the female reproductive structure, is present in gymnosperms.
- **Antheridia**: While antheridia (male reproductive structure) are not well-developed in gymnosperms, they are not completely absent; instead, they are reduced.

**Conclusion**: All statements regarding gymnosperms are correct.

### Step 2: Analyze Angiosperms
- **Characteristics**:
- **Triploid Endosperm**: Angiosperms have a triploid endosperm, which provides nutrition to the developing embryo.
- **Embryo Sac**: The presence of a 7-celled female gametophyte known as the embryo sac is also correct.

**Conclusion**: Both statements regarding angiosperms are correct.

### Step 3: Analyze Algae
- **Characteristics**:
- **Embryo Stage**: Algae do not have an embryo stage.
- **Reproduction by Spores**: Algae reproduce by spores, which is a correct statement.

**Conclusion**: Both statements regarding algae are correct.

### Step 4: Analyze Mosses (Bryophytes)
- **Characteristics**:
- **Independent Gametophyte**: The gametophyte stage in mosses is indeed independent.
- **Biflagellate Gametes**: Mosses produce biflagellate gametes that require water for movement.
- **Reproduction by Accessory Spores**: This statement is incorrect. Accessory spores are characteristic of panchay, not bryophytes.

**Conclusion**: The statement about reproduction by accessory spores is incorrect for mosses.

### Final Answer
The wrong combination is option D, which states that mosses reproduce by accessory spores.

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