How many true breeding pea plant varieties were selected by Mendel ?

How many true breeding pea lines were selected by Mendel in his experiments?

How many true breeding pea plant varieties did Mendel select aa pairs, which were similar except in one character with contrasting traits ?

How many true breeding pea plant varieties did Mendel select aa pairs, which were similar except in one character with contrasting traits ?

How many true breeding varieties of garden pea plant did Mendel select for starting his experiments?

How many pairs of constrasting characters in pea plants were selected by Mendel for his experiments on heredity ?

The contrasting traits with respect to seeds in pea plant that were studied by Mendel are