In lysosomes ,
a. The acidic condition is maintained by pumping protons to the exterior part.
b. Intercellular digestion occurs .
c. All types of macromolecules are digested .
d. The enzymes. Present in vesicles belong to acid hydrolases.
Select those statements which are correct .

Options

A. c and d
B. a and d
C. a and b
D. b and d

Answer

To solve the question regarding lysosomes, we need to evaluate each statement provided and determine which ones are correct.

### Step-by-Step Solution:

1. **Statement A: The acidic condition is maintained by pumping protons to the exterior part.**
- This statement is incorrect. Lysosomes maintain an acidic environment (pH around 4.8) by pumping protons (H⁺ ions) from the cytosol (the interior of the cell) into the lysosome, not to the exterior. Therefore, this statement is false.

2. **Statement B: Intercellular digestion occurs.**
- This statement is also incorrect. Lysosomes are involved in intracellular digestion, meaning they digest materials within the cell, such as worn-out organelles or engulfed pathogens. Therefore, this statement is false.

3. **Statement C: All types of macromolecules are digested.**
- This statement is correct. Lysosomes contain various enzymes (acid hydrolases) that can break down all types of macromolecules, including proteins, nucleic acids, carbohydrates, and lipids. Therefore, this statement is true.

4. **Statement D: The enzymes present in vesicles belong to acid hydrolases.**
- This statement is correct. The enzymes found in lysosomes are indeed known as acid hydrolases, which function optimally in the acidic environment of the lysosome. Therefore, this statement is true.

### Conclusion:
The correct statements are **C and D**.