Test cross in plants or in Drosophila involves crossing

An allele is said to be dominant if

If dwarf pea plant was treated with Gibberellic acid, it grew as tall as the pure tall pea plant. If this treated plant is crossed with a pure tall plant then the phenotypic ratio of is likely to be

The production of gametes by the parents, the formation of zygotes the $F_1$ and $F_2$ plants, can be understood using

Which one of the following can be explained on the basis of Mendel's Law of Dominance?

$A$. Out of one pair of factors one is dominant and the other is recessive.

$B$. Alleles do not show any expression and both the characters appear as such in $F_2$ generation.

$C$. Factors occur in pairs in normal diploid plants.

$D$. The discrete unit controlling a particular character is called factor.

$E$. The expression of only one of the parental characters is found in a monohybrid cross.

Choose the correct answer from the options given below:

In a plant, black seed color $(\mathrm{BB} / \mathrm{BB})$ is dominant over white seed color ($bb$). In order to find out the genotype of the black seed plant, with which of the following genotype will you cross it?