The Romans:

A. used trepanning to allow evil sprits to escape the minds of the ill

B. documented medical procedures to create the first medical textbooks

C. believed illness was caused by microorganisms

D. improved sanitation by building aqueducts

the answer is B. because the Roman's were frequently conquering their surrounding territories for greater power, they found it necessary to document medical procedures for future generations to learn these skills and keep their armies in good health for the next battle.