Textbook Problem

In sweet pea plants, an allele for purple flowers. (P) is dominanl when paired with a recessive allele for red flowers (p). An allele for Jang pollen grains (L) is dominant when paired with a recessive allele for round pollen grains (L). Bateson and Punnett crossed a plant having purple flowers and long pollen grains with one having white flowers and round pollen grains. All F₁ offspring have purple flowers and long pollen grains. Among the F₂ generation, the researchers observed the following phenotypes:

296 purple flowers/long pollen grains

19 purple /lower/ round pollen grains

27 red flowers/long pollen grains

85 red flowers/round pollen grains

What is the best explanation for these results?