Explanation:

- The scheme in question is aimed at bringing a 'Blue Revolution' by focusing on sustainable development in the fisheries sector.

- It proposes a significant investment of Rs 20,050 crore.

- This investment is projected for a period of five years.

- The task is to determine during which period this investment is planned.

Now, let's look at the options:

1. 2020-21 to 2025-26: This option spans six years, not five.

2. 2021-22 to 2024-25: This option only covers four years.

3. 2021-22 to 2025-26: This is a five-year period.

4. 2020-21 to 2024-25: This is also a five-year period.

5. 2021-22 to 2023-24: This option spans three years.