*Question G7C07:
What term specifies a filter’s attenuation inside its passband?*  

*Correct Answer is  A: Insertion loss*  

### AI Response: (may contain errors)  

In the context of filters, the term "insertion loss" refers to the amount of signal power lost when a filter is inserted into a circuit. This loss occurs within the filter's passband, which is the range of frequencies that the filter is designed to allow through with minimal attenuation.

### Explanation:

1. **Correct Answer: Insertion Loss**
   - **Insertion Loss** is the reduction in signal strength within the passband of a filter. It is typically measured in decibels (dB) and represents how much signal is lost due to the filter's presence. The formula for insertion loss is:
     $$ \text{Insertion Loss (dB)} = 10 \log_{10} \left( \frac{P_{\text{in}}}{P_{\text{out}}} \right) $$
     where $P_{\text{in}}$ is the input power and $P_{\text{out}}$ is the output power.

2. **Why the Other Choices are Incorrect:**
   - **Return Loss**: This term describes how much power is reflected back to the source due to impedance mismatches. It is not related to the attenuation within the passband.
   - **Q (Quality Factor)**: This is a measure of a filter's selectivity and bandwidth relative to its center frequency. It does not directly describe attenuation within the passband.
   - **Ultimate Rejection**: This term refers to the filter's ability to attenuate signals outside its passband, not within it.

Understanding these terms helps in identifying the characteristics and performance of filters in radio frequency applications.