Answer:
The correct answer would be B. The trait could show up in two different forms.
Alleles refer to the alternative forms of the gene. Different alleles of a gene code for different traits in an organism.
For example, T codes for tallness and t codes for a dwarf. Similarly, R codes for round seed shape and r codes for wrinkled seed shape et cetera.
Based on the expression levels, the alleles can be of two types recessive and dominant.
The allele which expresses itself in a heterozygous condition is said to be a dominant allele and the allele which is masked in heterozygous condition is said to be a recessive allele.