_________ is a process through which , over a long period of time, the organisms evolved adaptions to optimise its survival and reproduction in its habitat.

Explanation

The answer to the question is **Natural Selection**. Here’s a step-by-step breakdown of the reasoning:

1. **Understanding the Question**: The question asks for a process that leads to the evolution of organisms over a long period, focusing on adaptations that enhance survival and reproduction in their habitats.

2. **Identifying Key Terms**: The key terms in the question are "process," "long period of time," "organisms evolved," "adaptations," "survival," and "reproduction."

3. **Linking to Evolution**: The question pertains to a fundamental concept in biology that explains how species change over time. This concept is central to evolutionary biology.

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