Which of the following are characteristics of living beings ?
(i) Respiration
(ii) Reproduction
(iii) Adaptation
(iv) Excretion
Choose the correct answer from the options below:

Options

A. (i), (ii) and (iv) only
B. (i) and (ii) only
C. (ii) and (iv) only
D. (i), (ii), (iii) and (iv)

Answer

To determine which of the following are characteristics of living beings, let's analyze each option provided:

1. **Respiration**: This is a vital process for living organisms. During respiration, organisms exchange gases (like oxygen and carbon dioxide) and obtain energy necessary for survival. Therefore, respiration is a characteristic of living beings.

2. **Reproduction**: This is another essential characteristic of living beings. Reproduction is the biological process through which new individuals are produced from their parents, ensuring the continuation of a species. Thus, reproduction is also a characteristic of living beings.

3. **Adaptation**: Living beings have the ability to adapt to their environment. This means they can change or adjust their behavior, physiology, or structure to survive in changing conditions. Hence, adaptation is a characteristic of living beings.

4. **Excretion**: This process involves the removal of metabolic waste from the body. Living organisms must eliminate waste products to maintain homeostasis and function properly. Therefore, excretion is also a characteristic of living beings.

Now, summarizing the characteristics identified:
- Respiration: Yes
- Reproduction: Yes
- Adaptation: Yes
- Excretion: Yes

Since all four options (i, ii, iii, iv) are characteristics of living beings, the correct answer includes all of them.

### Final Answer:
All of the above options (i, ii, iii, iv) are characteristics of living beings.

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