題幹已經說 It is too
expensive for farmers to use routinely, and since it is not effective until a
month after vaccination, administering it after an outbreak begins helps very
little.
也就是說不只是「施打次數」會很少，而且這少數的「施打時機」也很難加以掌握。
A 跟 B 都無助於「施打時機」的掌握，只有 E 可以。
※ 引述《Zentigra (Amygdala)》之銘言：
: Outbreaks of Rift Valley fever occur irregularly in East Africa, several
: years apart. When outbreaks do occur, they kill thousands of cattle. A
: livestock vaccine against the disease exists but is rarely used. It is too
: expensive for farmers to use routinely, and since it is not effective until a
: month after vaccination, administering it after an outbreak begins helps very
: little. Nevertheless, experts predict that use of the vaccine will increase
: significantly within the next few years.
: Which of the following, if true, provides the strongest justification for the
: experts’ prediction?
: A. Rift Valley fever is spread by mosquitoes, but each outbreak is so
: widespread that it is impractical to control it by using insecticides.
: B. When an outbreak of Rift Valley fever occurs, unaffected countries
: often refuse to import livestock from the countries affected by the outbreak.
: E. Recently published research has shown that certain identifiable
: climatic conditions are almost invariably followed, within two to five
: months, by an outbreak of Rift Valley fever
: Answer 是E, 請問如何排除A跟B呢
: A--> 無法透過控制病原的方式減輕疫情, 所以需要疫苗 (似乎合理?)
: B--> farmer的生意被impact, 所以increase demand for vaccine (似乎也合理?)
: Thanks
--
雲扉松徑長寂寥
只有幽人自來去
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 1.163.225.250