When Mendel’s first generation pea plants were allowed to self-pollinate, the ratio of tall (dominant) to short (recessive) plants in the second generation was

3:1

Explanation:

Gregor Mendel, who is regarded as the Father of Genetics, worked with pea plants throughout his research. He observed the trait for height in the plants. In the gene for height in pea plants, the allele for tallness (T) is dominant over the allele for shortness (t).

Mendel's first generation pea i.e. F1 plants, which were derived by crossing tall (TT) and short (tt) parents in the P generation, were heterozygous for tallness (Tt). When these F1 plants were allowed to self pollinate i.e. Tt × Tt, the following proportion of offsprings were produced in the F2 generation:

- TT, Tt, Tt, and tt

- Tall 3 : short 1

the answer would be d