A bell-shaped distribution like this is best explained by:
- Acheck_circle
Polygenic inheritance with additive contributions from multiple gene loci.
- B
Mitochondrial inheritance.
- C
Strict Mendelian dominance with two phenotypic classes.
- D
Sex linkage.
Explanation
Continuous variation across many phenotypic classes arises when many genes contribute small additive effects, often with environmental modifiers.