题目解析:
题干提问“Akimel O'odham culture”,定位 By the time the Spanish arrived in the region in the sixteenth century, they met Amerindians called Akimel O’odham, who were still practicing a form of irrigation, but not on the enormous scale developed by the Hohokam. 得知 Akimel O'odham 仍然延续着 Hohokam 的灌溉体系,只不过没有 Hohokam 规模大。由 still 可理解为“延续前人行为”,对应 B 的 evolved from,故选 B。A 的 more extensive 与原文 not on the enormous scale 说反,C 的 destroyed the Hohokam culture、D 的 not as environmentally conservative 均未提及。