题目选项分析

The area west of Springfield was a smelting factory from 1879 until 1962, when it was purchased by Manfred Otterbein, the noted philanthropist and animal lover, who established a wildlife refuge on the property and used one of the existing buildings as a rare bird sanctuary.

The area west of Springfield was a smelting factory from 1879 until 1962, when it was purchased by Manfred Otterbein, the noted philanthropist and animal lover, who had established a wildlife refuge on the property, using one of the existing buildings to be a rare bird sanctuary.