Pinus plant has 1st year, 2nd year and 3rd year cones. In which cone does fertilisation occur?

Explanation

### Step-by-Step Solution:

1. **Understanding Pinus**: Pinus is a gymnosperm, which means it is a non-flowering plant. In gymnosperms, seeds are not enclosed in an ovary, and thus, there is no fruit formation.

2. **Reproductive Structures**: The reproductive structures of Pinus are called cones. There are two types of cones: male cones (which produce pollen) and female cones (which produce ovules).

3. **Female Cone Function**: The female cone, also known as the megasporangium or megastrobulus, is responsible for producing ovules. These ovules are the unfertilized seeds.

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