(B) Mr. Basco and Mrs. Roberts
(C) Mr. Jefferson and Mrs. Parda
(D) Mr. Jefferson and Mrs. Basco
(E) Mr. Roberts and Mrs. Jefferson
11. If, after the first two calls of the dance, each dancer is again partnered with his or her own spouse, the calls made could have been
(A) X followed by Y
(B) Z followed by X
(C) X followed by X, or Y followed by Y, or Z followed by Z
(D) X followed by X, or Y followed by Y, but not Z followed by Z
(E) X followed by X, or Z followed by Z, but not Y followed by Y
12. If, since the beginning of the dance, two partner changes have been made, the first in response to call X and the second in response to call Y, which of the following must be true?
(A) Mrs. Basco is partnered with Mr. Roberts.
(B) Mrs. Jefferson is partnered with Mr. Jefferson.
(C) Mr. Parda is partnered with Mrs. Roberts.
(D) Only two of the women are partnered with their husbands.
(E) No man is partnered with his wife.
13. If Mr. Basco is partnered with Mrs. Basco after the first two calls of the dance, and if the second call was Y, which of the following is true of the first call?
(A) It must have been X.
(B) It must have been Y.
(C) It must have been Z
(D) It could have been any of the three calls except X.
(E) It could have been any of the three calls except Z.
14. If Mr. Jefferson is partnered with Mrs. Basco after the first two calls of the dance, and if the second call was Z, which of the following is true of the first call?
(A) It must have been X.
(B) It must have been Y.
(C) It must have been Z.
(D) It could have been any of the three calls except Y.
(E) IT could have been any of the three calls except Z.
15. If the dance begins with the three calls Z, X, and Y, in the order given, it must be true that after the third call.
(A) Mr. Parda partners Mrs. Jefferson
(B) Mr. Parda partners Mrs. Roberts
(C) Mr. Basco partners Mrs. Basco
(D) Mr. Basco partners Mrs. Jefferson
(E) Mr. Basco partners Mrs. Roberts