Direction () : In the following passage, there are blanks, each of which has been numbered. These numbers are printed below the passage and against each, five words are suggested, one of which fits the blank appropriately.
Invasive pests and weeds can (###B1###) country by flying over the border or by simply growing gratuitously. In such cases, (###B2###) their entry is difficult. However, when they land up at airports and dockyards in cargos of imported grain or with items carried by
tourists, the authorities should be able to (###B3###) them out. For this reason, countries have animal, plant and health quarantine facilities at all transborder entry points. Tanzania, however, seems to have let its guard (###B4###) late, especially with regards to agricultural products, which form the bulk of its imports. It is difficult to establish how pests and weeds are entering the country. What is (###B5###) is that there is no institutional mechanism to even probe these invasions. The concerned ministry has not (###B6###) a single invasion till date.