Which of the following statements are true about amphibians?
a. they are cold-blooded
b. Respiration occurs through gills, skin and lungs.
c. they are poikilotherms
d. Respiration occurs only through gills and skin.

Options

A. a & d
B. c & d
C. a,b & c
D. a & c

Explanation

To determine which statements about amphibians are true, we will analyze each statement one by one:

1. **Statement A: They are cold-blooded.**
- Amphibians are indeed cold-blooded animals, meaning they cannot regulate their body temperature internally and rely on environmental temperatures. This statement is true.

2. **Statement B: Respiration occurs through gills, skin, and lungs.**
- Amphibians have a unique respiratory system that allows them to breathe through gills (when they are in the larval stage), skin (cutaneous respiration), and lungs (in adult forms). Therefore, this statement is also true.

3. **Statement C: They are poikilotherms.**
- The term "poikilotherm" refers to animals whose body temperature varies with the temperature of their environment. Since amphibians cannot regulate their body temperature, this statement is true as well.

4. **Statement D: Respiration occurs only through gills and skin.**
- This statement is incorrect because, as mentioned earlier, adult amphibians also possess lungs for respiration. Thus, they do not rely solely on gills and skin for breathing.

**Conclusion:**
The true statements about amphibians are:
- A: They are cold-blooded (True)
- B: Respiration occurs through gills, skin, and lungs (True)
- C: They are poikilotherms (True)
- D: Respiration occurs only through gills and skin (False)

Therefore, the correct options are A, B, and C.

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