Life cycle of seed plants is

Options

A. Haplontic
B. Haplo-diplontic
C. Diplontic
D. Diplo-haplontic

Answer

### Step-by-Step Solution:

1. **Understanding the Life Cycles**: The life cycle of seed plants can be categorized into four types: haplontic, haplodiplontic, diplontic, and diplohaplontic. Each of these terms describes the dominance of either the haploid (n) or diploid (2n) phase in the life cycle of an organism.

2. **Identifying Seed Plants**: Seed plants are primarily divided into two major groups: gymnosperms (e.g., Cycas and Pinus) and angiosperms (flowering plants). Both groups exhibit a specific type of life cycle.

3. **Determining the Life Cycle of Seed Plants**: Among the four types of life cycles mentioned, seed plants predominantly exhibit a **diplontic life cycle**. In this cycle, the sporophytic phase (2n) is the dominant phase, meaning that the plant spends most of its life in the diploid state.

4. **Characteristics of the Diplontic Life Cycle**: In the diplontic life cycle, the sporophyte is photosynthetic and is the main plant body that we observe. The gametophyte (haploid phase) is usually reduced and dependent on the sporophyte.

5. **Conclusion**: Therefore, the life cycle of seed plants is classified as diplontic, where the diploid sporophyte is the dominant phase.