The process which prevents interbreeding between related groups of living organisms is called …...............

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the process preventing interbreeding between related groups of living organisms.

2. **Identifying the Key Concept**: The key concept here is the idea of preventing interbreeding. This relates to how species can diverge and become distinct from one another.

3. **Defining the Term**: The term that describes this process is "isolating mechanism." Isolating mechanisms are biological features that prevent species from mating and producing offspring.

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