12. The success of the program to eradicate smallpox has stimulated experts to pursue what they had not previously considered possible -- better control, if not eradication, of the other infections such as measles and yaws.

A. what they had not previously considered possible -- better control, if not eradication, of the other infections such as
B. what they had not previously considered a possibility -- better control, if not eradication, of such infections like
C. something they had not previously considered possible -- better control, if not eradication, of such infections as
D. something not considered a previous possibility -- better control and perhaps eradication, of other infections such as
E. the possibility of what they had not previously considered possible – better control and possibly eradication of infections like

there are already two threads dedicated to this problem, containing some 16 posts between them.
http://www.manhattangmat.com/forums/the-success-of-the-program-to-eradicate-smallpox-t1161.html
http://www.manhattangmat.com/forums/program-to-eradicate-smallpox-has-stimulated-experts-t1822.html

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