The growth of the following system per unit time which is expressed on a common basis or per unit initial parameter is known as

Options

A. Absolute growth rate
B. Relative growth rate
C. Both (a) and (b)
D. Exponential growth rate

Answer

To solve the question, we need to determine what the term is for the growth of a system per unit time, expressed on a common basis or per unit initial parameter.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Absolute Growth Rate**: This refers to the total growth of a system over a specific period of time without considering the initial size of the system. It is simply the difference in size before and after a certain time period.
- **Relative Growth Rate**: This measures the growth of a system in relation to its initial size. It indicates how much the system grows per unit time relative to its initial size.
- **Exponential Growth Rate**: This describes a specific growth pattern where the growth rate of a value is proportional to its current value, leading to growth that accelerates over time.

2. **Analyzing the Options**:
- **Option 1: Absolute Growth Rate** - This is incorrect because it does not take into account the initial size of the system.
- **Option 2: Relative Growth Rate** - This is correct as it measures growth per unit time relative to the initial parameter.
- **Option 3: Both A and B** - This is incorrect since only one of the options (Relative Growth Rate) is correct.
- **Option 4: Exponential Growth Rate** - This is also incorrect as it refers to a specific growth pattern rather than a general measure of growth per unit time.

3. **Conclusion**:
- The correct answer is **Option 2: Relative Growth Rate**, as it accurately describes the growth of a system per unit time expressed on a common basis or per unit initial parameter.

### Final Answer:
**Relative Growth Rate** (Option 2)