Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous `CuSO_(4)` and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the followig statement (s) is (are) correct?
1. In beakers A and B, exothermic process has occurred.
2. In beakers A and B, endothermic process has occurred.
3. In beaker C, exothermic process has occurred.
4. In beaker C, endothermic process has occurred.

Options

A. Only 1
B. Only 2
C. 1 and 4
D. 2 and 3

Explanation

To solve the problem, we need to analyze the observations made in the three beakers after adding different substances.

### Step-by-Step Solution

1. **Understanding the Beakers:**
- Beaker A: Contains NaOH.
- Beaker B: Contains anhydrous CuSO₄.
- Beaker C: Contains NaCl.
- Each beaker has 25 mL of water.

2. **Observations:**
- Beakers A and B show an increase in temperature.
- Beaker C shows a decrease in temperature.

3. **Identifying the Type of Reactions:**
- **Exothermic Reaction:** A reaction that releases heat, resulting in an increase in temperature of the solution.
- **Endothermic Reaction:** A reaction that absorbs heat, resulting in a decrease in temperature of the solution.

4. **Analyzing Beaker A (NaOH):**
- When NaOH is dissolved in water, it releases heat (exothermic reaction).
- Therefore, the temperature increases in Beaker A.

5. **Analyzing Beaker B (Anhydrous CuSO₄):**
- When anhydrous CuSO₄ is added to water, it also releases heat (exothermic reaction).
- Thus, the temperature increases in Beaker B.

6. **Analyzing Beaker C (NaCl):**
- When NaCl is dissolved in water, it absorbs heat from the surroundings (endothermic reaction).
- This leads to a decrease in temperature in Beaker C.

7. **Conclusion:**
- From the observations:
- In Beaker A, an exothermic process has occurred.
- In Beaker B, an exothermic process has occurred.
- In Beaker C, an endothermic process has occurred.
- Therefore, the correct statements are:
- Statement 1: In beakers A and B, exothermic process has occurred. (Correct)
- Statement 2: In beakers A and B, endothermic process has occurred. (Incorrect)
- Statement 3: In beaker C, exothermic process has occurred. (Incorrect)
- Statement 4: In beaker C, endothermic process has occurred. (Correct)

### Final Answer:
The correct statements are:
1. In beakers A and B, exothermic process has occurred.
4. In beaker C, endothermic process has occurred.