Nutrition includes the study of:

Options

A. the organism's food
B. process of digestion
C. the way an organism obtains food
D. all of the above

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Nutrition**: Nutrition is the study of how organisms obtain and utilize food to gain energy and support their bodily functions.

2. **Components of Nutrition**:
- **Food Sources**: Nutrition involves understanding the types of food that organisms consume. This can include plants, animals, and other sources.
- **Energy Provision**: The primary purpose of nutrition is to provide energy to organisms, which is essential for their survival and daily activities.

3. **Digestion Process**:
- The process of digestion is a crucial aspect of nutrition. It involves breaking down food into smaller, absorbable components.
- Different enzymes are released during digestion to facilitate the breakdown and absorption of food materials.

4. **Types of Organisms**:
- **Autotrophs**: These are organisms, primarily plants, that can produce their own food through processes like photosynthesis.
- **Heterotrophs**: These are organisms, mainly animals, that cannot produce their own food and depend on other organisms (plants or other animals) for nutrition.

5. **Importance of Nutrition**: Nutrition is vital for all organisms as it provides the necessary energy for growth, maintenance, and daily activities.

6. **Conclusion**: In summary, nutrition encompasses the study of food sources, energy provision, digestion processes, and the classification of organisms based on their food acquisition methods.

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