Which plants in this figure must all be heterozygous?

Question

Quizplus · Accepted Answer

The F1 generation is the result of crossing two homozygous parents with contrasting traits. In this case, a true-breeding purple-flowered plant (homozygous dominant) is crossed with a true-breeding white-flowered plant (homozygous recessive). The resulting offspring (F1 generation) are all heterozygous for flower color (Pp). Therefore, all purple-flowered plants in the F1 generation must be heterozygous (Pp).

Which Plants in This Figure Must All Be Heterozygous