The exchange of segments of DNA between the members of a pair of chromosomes
1. acts as a source of variations within a species.
2. is called crossing
3. ensures that variations within a species never occur.
4. always produces genetic disorders.

Please help I’ll give

As I think Option B is the correct one

Explanation:

An exchange of chromosome segments between non-sister homologous chromatids occurs and is called crossing over. The crossover events are the first source of genetic variation produced by meiosis. ... Crossover occurs between non-sister chromatids of homologous chromosomes.

The exchange of segments of DNA between the members of a pair of is called crossing

hope it is helpful to you

answer; i believe the answer is (polygenic inheritance;

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