空欄に入る選択肢とその理由を教えていただきたいです。 Experts say that the huge success of Japanese animation in the U.S. is (17) the "media-mix" marketing strategy of the industry. Japanese companies not only (18) the animation, but they also sell cards and computer games with the same characters. (19) 17. (A) on to (B) due to (C) next to (D) as to 18. (A) broad (B) abroad (C) broadcast (D) broaden 19. (A) Were it not for this strategy, they would succeed. (B) Because of this strategy, the US animation industry will be more successful. (C) If they had used this strategy, they could have achieved that success. (D) Without this strategy, that success would have been impossible.