Test-retest reliability refers to a measure of reliability:
a) obtained by administering different versions of an assessment tool to the same group of individuals.
b) used to assess the degree to which different judges or raters agree in their assessment decisions.
c) used to evaluate the degree to which different test items that probe the same construct produce similar results.
d) obtained by administering the same test twice over a period of time to a group of individuals.

A

Explanation:

Obtained by administering the same test twice over a period of time to a group of individuals.

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