Which one of the following cannot be explained on the basis of Mendel’s law of dominance?

An allele is said to be dominant if

In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeded plant is crossed with a green seeded plant, what ratio of yellow and green seeded plants would you expect in $F_1$ generation?

If a cross is made between $AA$ and $aa$, the nature of ${F_1}$ progeny will be

Which of the following statements are false?

$I.$ A Dominant allele determines the phenotype when paired with a recessive allele

$II.$ A recessive allele is weaker than a dominant allele

$III.$ A recessive allele do not shows its effects when paired with a dominant allele

$IV.$ A dominant allele is always better for an organism