The is a research strategy that minimizes the potential methodological problems associated with the placebo effect and experimenter bias.

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.

many citizens are in danger of contracting a food-borne illness.

more people are living with chronic illnesses.

pathogens are becoming stronger and harder to defeat.

edge nuity

the correct answer is a