Which of the following statements are true for flowers?
(i) Flowers are always bisexual.
(ii) They are the sexual reproductive organs.
(iii) They are produced in all groups of plants.
(iv) After fertilisation they give rise to fruits.

Options

A. (i) and (iv)
B. (ii) and (iii)
C. (i) and (iii)
D. (ii) and (iv)

Explanation

To determine which statements about flowers are true, let's analyze each statement one by one:

1. **Statement (i): Flowers are always bisexual.**
- This statement is **false**. While many flowers are bisexual (containing both male and female reproductive organs), there are also unisexual flowers that contain only male or only female organs. Therefore, not all flowers are bisexual.

2. **Statement (ii): They are the sexual reproductive organs.**
- This statement is **true**. Flowers are indeed the sexual reproductive organs of flowering plants (angiosperms). They facilitate the processes of pollination and fertilization, leading to the production of seeds.

3. **Statement (iii): They are produced in all groups of plants.**
- This statement is **false**. Not all groups of plants produce flowers. For example, non-flowering plants such as ferns and mosses reproduce through spores rather than flowers.

4. **Statement (iv): After fertilization they give rise to fruits.**
- This statement is **true**. After fertilization occurs in flowers, they often develop into fruits, which contain seeds. This is a key part of the reproductive cycle in flowering plants.

### Summary of the Analysis:
- Statement (i): False
- Statement (ii): True
- Statement (iii): False
- Statement (iv): True

### Conclusion:
The true statements about flowers are (ii) and (iv).

### Final Answer:
The correct statements are (ii) and (iv).

---