Rice Plants May Be Tolerant or Intolerant to Flooding

Multiple Choice

Rice plants may be tolerant or intolerant to flooding. A true-breeding tolerant plant was crossed with a true-breeding intolerant plant, and approximately 75% of the F₁ generation was tolerant to flooding. What does this most likely suggest about the flood-tolerant and flood-intolerant alleles? ​

A) Multiple alleles control flood-tolerance.
B) The alleles for flood-tolerance and flood-intolerance are codominant.
C) The allele for flood-tolerance is incompletely dominant. ​
D) The allele for flood-intolerance is dominant, while the allele for flood-tolerance is recessive. ​
E) The allele for flood-tolerance is dominant, while the allele for flood-intolerance is recessive. ​