A population of a wild herbaceous plant displays continuous variation in mature leaf surface area, showing a normal distribution.
Which of the following genetic and environmental descriptions cannot account for this continuous variation?
The trait is controlled by a single gene with two alleles showing complete dominance, with leaf development occurring under completely uniform environmental conditions.
The trait is controlled by several genes on different chromosomes that have small, cumulative effects on leaf development.
The trait is controlled by a single gene with two codominant alleles, with leaf size being highly sensitive to localized microclimatic variations.
The trait is controlled by multiple epistatic genes whose interactions are modified by abiotic factors such as soil nitrogen level.