Answer: The correct answer is-
The phenotype ( physical appearance) for the F1 generation is Purple petals.
As per the information in the question, the genotypes of parent plants are-
PP ( showing purple petals) and pp ( showing white petals).
This indicates that purple petals is a dominant trait ( expressed by capital letter allele).
White petal is a recessive trait (expressed by small letter allele)
A dominant trait masks the expression of recessive trait. Purple petal can have two genotypes that is Pp ( heterozygous dominant) and PP ( homozygous dominant) whereas white petal will exhibit only in the genotype pp ( homozygous recessive).
When these two parents are crossed, they will produce all plants with purple petal ( genotype Pp) in F1 generation.