Final answer:
The probability of the offspring having wrinkled seeds is 25%.
Step-by-step explanation:
When two plants with round seeds are crossed, the offspring can have either round or wrinkled seeds. The probability of an offspring having wrinkled seeds can be determined using a Punnett square. In this case, since both plants are heterozygous for seed shape, their genotype would be Rr. The Punnett square for this cross would yield a 25% chance of offspring having wrinkled seeds.
Learn more about Probability of seed shape inheritance