Final answer:
The correct term for the process where nitrogen is incorporated into organic molecules is nitrogen fixation, which is essential for plant growth and agriculture.
Step-by-step explanation:
The process by which nitrogen is incorporated into organic molecules is known as nitrogen fixation. This process is crucial for converting atmospheric nitrogen (N₂) into a form that plants can utilize, such as ammonia (NH₃). Nitrogen fixation is essential for agricultural production since nitrogen is a vital component for the synthesis of nucleotides and proteins within plants. Essentially, nitrogen-fixing bacteria, which are often found in the root nodules of legumes or in the soil, convert nitrogen gas into organic compounds that can then be taken up by plants, leading to increased crop yields and the ability to compete with weeds. Therefore, the correct answer to the question is a) Nitrogen Fixation.