If we start to play a "what, if" game we can assume that #1 reads as "X descends 9 times faster than Y ascends" and the answer would be (D), because #1 is also sufficient
#1 is NOT sufficient. If Y scales up by a factor of 2, so does X and they APPROACH each other quicker.
Former Senior Instructor, Manhattan GMAT and VeritasPrep
Vice President, Midtown NYC Investment Bank, Structured Finance IT
MFE, Haas School of Business, UC Berkeley, Class of 2005
MBA, Anderson School of Management, UCLA, Class of 1993