Jennifer Substantially Performs Her Service Contract with Gretchen

Jennifer substantially performs her service contract with Gretchen.Due to Jennifer's failure to render complete performance,Gretchen

A) is discharged from any further contractual obligations.
B) is required to pay the full contract price, minus the value of Jennifer's defective performance.
C) is required to pay the full contract price.
D) may declare a material breach and pay only for the value received.