Those enzymes which are active inside a cell are called extra-cellular enzymes.
Enzymes lower the rate of biological activities.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question regarding the assertion and reasoning about enzymes, we will break it down into clear steps.

### Step-by-Step Solution:

1. **Identify the Assertion**: The assertion states that "those enzymes which are active inside a cell are called extracellular enzymes."

- **Analysis**: This statement is incorrect. Enzymes that function within the cell are referred to as **intracellular enzymes**. In contrast, **extracellular enzymes** are those that are secreted outside the cell to catalyze reactions in the external environment.

2. **Identify the Reason**: The reason provided is "enzymes lower the rate of biological activities."

- **Analysis**: This statement is also incorrect. Enzymes act as catalysts and actually **increase** the rate of biochemical reactions, not lower it. They facilitate and speed up biological processes by lowering the activation energy required for reactions to occur.

3. **Conclusion**: Since both the assertion and the reason are incorrect, we can conclude that the correct answer to the question is that both statements are false.

4. **Final Answer**: The answer to the question is **Option 4**, which states that both the assertion and reason are incorrect.