Give correct term for the following statements:
Inability of a functional male and female gametes to achieve fertilisation on being brought close together

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the correct term that describes the situation where functional male and female gametes are unable to achieve fertilization even when they are brought close together.

2. **Identifying the Process of Fertilization:**
Normally, when male and female gametes come into proximity, they undergo fertilization, leading to the formation of a zygote. This is a crucial step in sexual reproduction.

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