The party-in-the-electorate is made up of people who a) pass the initiation test into the party b) obey the party's rules and pay membership fees c) campaign door-to-door on behalf of a party's candidates d) vote for a party's candidates

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

the answer is d.index