After heated debates and discussions, the government was finally persuaded to consider another 19 effective method: giving the pigeons birth control.
答案：(D) similarly
語意「另一個『同樣』有效的方法」，similarly（同樣地）符合，暗示這個新方法跟原本的方法一樣有效（但更人道）；nearly（幾乎）、shortly（不久）、precisely（精確地）都不合。
another ___ effective method，四個副詞都能修飾 effective，讀起來都不奇怪，所以容易憑語感隨手挑。這一格的線索不在這句話裡——要判斷的是新方法和舊方法之間的關係，而舊方法寫在前面兩句。
往前找舊方法：gathering the birds and shooting them（聚集後射殺），接著 that idea led to strong protests from numerous animal rights groups（引發動保團體強烈抗議）。所以政府換方法的理由是「不人道」，不是「沒效」。既然舊方法本身有效，新方法就要說成「一樣有效」，這就是 similarly effective。 空格前的 another（另一個）也在暗示：這是同一類（同樣有效）之中的另一個選擇。
nearly effective（幾乎有效）暗示新方法效果打了折扣，但最後一段預測四五年內減少七到八成，效果很好；shortly（不久）是時間副詞，不能拿來修飾 effective 的程度；precisely（精確地）用來修飾數字或描述，修飾 effective 語意不通。
similarly（同樣地）、be similar to（與……相似）、equally effective（同樣有效）、lead to（導致）、an effective method（有效的方法）、protest against（抗議……）。
Street pigeons are a common sight in many European cities. In fact, a visit to a major European city just would not be the same 16 encountering them: bathing in fountains, perching on historic buildings, and flocking in public squares. In Barcelona, however, the birds are now threatening to 17 the city's historic center, pooping on monuments, buildings, and even tourists.
The city council originally proposed 18 the pigeon population by gathering the birds and shooting them. But that idea led to strong protests from numerous animal rights groups. After heated debates and discussions, the government was finally persuaded to consider another 19 effective method: giving the pigeons birth control.
In 2016, the city council decided to put its 85,000 pigeon population on a birth control pill to block the formation of eggs in birds. Starting from April 2017, the pills were placed in 40 bird feeders 20 throughout the city. It was predicted that there would be a decrease of 20 percent in the pigeon population in the first year and between 70 and 80 percent in four or five years.