About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.
(A) States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering
(B) States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering
About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.
(A) States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering
(B) States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering
About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.
(A) States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering
(B) States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering
第一组差异点是 with milky sap是修饰a herbaceous plant还是修饰leafy spurge。但这里你或许不是很能确定。因为这一堆字你都不懂。没关系，一个题目不会只有一个解题点，不熟的点请务必先跳过，不要一开始就赌身家。
后方第二组差异点就相对熟悉很多了，是在考三个动作在语意上的关系：
A选项的结构是gives... , displacing ... and rendering...
B选项则是gives ...and displaces..., rendering...
这时再来读语意，你就知道重点了。 give mouth sores to cattle尽管不懂意思，但至少知道是影响牲口。 displaces grasses and other cattle food尽管不懂意思，但至少知道是影响植物。一个影响动物，一个影响植物，两件事的关系应该是并列独立的，而不是「影响动物所以连带影响到动物吃的植物」（如果要合理应该是倒过来吧？应该是影响动物吃的饲料才会去影响动物）。因此答案选B，而不是选A。