Full Explanation

Sentence Logic
The sentence describes the development of forensic pathology as a recognized discipline between 1870 and 1900. The evidence given is the founding of seven dedicated medico-legal institutes in just three decades-institutes that provided training and research facilities.

This evidence points to growth, establishment, and vitality in the field.
Why A. professionalization works:

Professionalization = the process of becoming an established, recognized profession with formal standards, training, and institutions.
The founding of dedicated institutes for autopsy training and toxicological research is exactly what professionalization looks like-formal structures, specialized training, and recognized standards.


Why E. flourishing works:

Flourishing = thriving, growing vigorously, being successful.
Seven new institutes in thirty years signals a field that is expanding and thriving.


Both words convey positive development and establishment, and they are close enough in meaning to satisfy Sentence Equivalence.

Why the Other Options Are Incorrect

B. stagnation - means lack of growth or movement. The opposite of founding seven new institutes.
C. proliferation - means rapid increase in number. While the institutes proliferated, the blank refers to the discipline itself. A discipline does not "proliferate" in the same way-it professionalizes or flourishes. Also, there is no synonym for "proliferation" among the remaining choices, so it cannot form a valid pair.
D. contraction - means shrinking. The opposite of what the evidence shows.
F. skepticism - means doubt. There is no mention of doubt or disbelief in the passage.