The reason for Mendel's success was his choice of pea plants for his experiments.

How many pairs of contrasting traits were selected by Mendel for his study on garden peas?

Which of the following is incorrect for garden pea?

If a dwarf plant is treated with a growth hormone and then crossed with a dwarf plant,what will be the phenotype of the $F_1$ generation?

Assertion: Cross of $F_1$ individual with recessive homozygous parent is test cross.
Reason: No recessive individuals are obtained in the monohybrid test cross.

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: In an experiment, Mendel observed that the $F1$ progeny plants are all tall and none are dwarf.
Reason $R$: Stem height is a contrasting trait, with tall being dominant and dwarf being recessive.
In the light of the above statements, choose the most appropriate answer from the options given below: