Related to the Economics in Practice on P

Related to the Economics in Practice on p. 50: The Amazon Kindle and the electronic textbooks available for the Kindle are complementary goods. Electronic textbooks and traditional, hard-copy textbooks are substitute products. If the price of electronic textbooks for the Kindle increases,

A) demand for the Kindle decreases, demand for electronic textbooks decreases, and demand for traditional, hard-copy textbooks increases.
B) the quantity of Kindles demanded decreases, demand for electronic textbooks decreases, and the quantity of traditional, hard-copy textbooks demanded increases.
C) demand for the Kindle increases, the quantity of electronic textbooks demanded decreases, and demand for traditional, hard-copy textbooks increases.
D) demand for the Kindle decreases, the quantity of electronic textbooks demanded decreases, and demand for traditional, hard-copy textbooks increases.