The answer is False!
P - dominant allele for inflated pods
p - recessive allele for inflated pods
PP - homozygote with inflated pods
Pp - heterozygote with inflated pods
pp - homozygote with inflated pods
S - dominant allele for round seeds
s - recessive allele for wrinkled seeds
SS - homozygote with round seeds
Ss - heterozygote with round seeds
ss - homozygote with wrinkled seeds
1. A Pea plant that is homozygous for inflated pods are heterozygous for round seeds: PPSs
2. A plant that is heterozygous for inflated pods and a homozygous for wrinkled seeds: Ppss
Let's look at their genotypes separately, and cross them that way:
Parents: PP x Pp
Offspring: PP PP Pp Pp
All of the offspring will have the same phenotype (100% = 1). So, this trait does not affect phenotypic ratio
Parents: Ss x ss
Offspring: Ss Ss ss ss
Half of the offspring will have wrinkled seeds and half of them will have round seeds: 50% : 50% = 1 : 1
So, the phenotypic ratio is not 1 : 3