18. The word "yield" in line 23 is closest in meaning to (A) imitate (B) produce (C) revise (D) contrast

20. According to the author, what made it possible for members of the general public to own prints in the sixteenth century? (A) Prints could be made at low cost. (B) The quality of paper and ink had improved. (C) Many people became involved in the printmaking industry. (D) Decreased demand for prints kept prices affordable.