Maize, also known as corn, has multiple uses. Let`s look at each option to better understand the uses of maize:

Option 1: It is used for the production of starch.

Maize is commonly used for starch production. Starch extracted from maize is used in various industries, including food processing, paper making, and textile manufacturing.

Option 2: It is used in the manufacture of poultry feed.

Maize is a primary component in poultry feed. It provides essential carbohydrates, proteins, and energy for poultry animals such as chickens and turkeys.

Option 3: It is used in producing bio-fuel.

Maize is one of the major crops used for biofuel production. Ethanol, a biofuel, can be produced from maize through a process called fermentation. Ethanol is used as a renewable energy source to power vehicles.

Based on the above explanations, it is evident that all three options are correct. Hence, the correct answer is option 4: 1, 2, and 3. Maize is used for the production of starch, in the manufacture of poultry feed, and in producing biofuel.