Explanation:

- Papaya:

- Papaya plants have unisexual flowers, meaning they have separate male and female flowers.

- Male flowers produce pollen, while female flowers develop into fruit after pollination.

- Hibiscus:

- Hibiscus flowers are bisexual, containing both male (stamen) and female (pistil) reproductive parts.

- This allows them to self-pollinate or cross-pollinate with other hibiscus flowers.

- Mustard:

- Mustard plants also have bisexual flowers.

- They contain both stamen and pistil, enabling self-pollination or cross-pollination.

- Sunflower:

- Sunflowers have composite flower heads consisting of numerous small bisexual flowers.

- These heads can self-pollinate or cross-pollinate.