Vicki is shopping for books. She prefers Great Expectations to The Chosen and prefers The Chosen to Jurassic Park. She buys Great Expectations and Jurassic Park for a total of $30. Which of the...

Vicki is shopping for books. She prefers Great Expectations to The Chosen and prefers The Chosen to Jurassic Park. She buys Great Expectations and Jurassic Park for a total of $30. Which of the following MUST be true?

a. Her PIBP for Jurassic Park is greater than $ 15.

b. Her PIBP for Great Expectations is greater than $ 15.

c. Her PIBP for Jurassic Park is less than $15.

d. None of the above.