In June of 1995, due to NASA technicians inspecting the space shuttle Discovery for an upcoming launch found over two hundred punctures in a fuel tank. Video surveillance revealed the culprits; two northern flickers, a species of woodpecker, was attempting to excavate a nest in the fuel tank’s foam insulation. Upon striking the solid metal beneath, the flickers would stubbornly choose a new spot and try again. (48)
[1] In the northern United States, where most flickers return each summer to mate and raise broods, the birds’ persistence is well known. [2] By lacking a distinct song, flickers drum their beaks against hard surfaces to announce themselves to mates. [3] The louder the noise an object makes, the more attractive it is to flickers. [4] Among their favorite noisemakers are drainpipes, TV antennas, and even farm equipment. [5] At the Kennedy Space Center in Florida, though the flickers’ persistence seemed mysterious. [6] Worse, it posed a serious risk. [7] For solid metal to stop the birds from trying to nest at the launch site, how could NASA prevent damage to its equipment and keep the species safe? (54)
NASA put together a committee, dubbed the Bird Investigation Review and Deterrent (BIRD) team, to consult with wildlife experts. After learning that flickers seek out soft, rotted wood when excavating nests, the team recommended the removal of dead trees from the area. For instance, upon learning that flickers forage for food on the ground, BIRD determined that tidy lawns made crawling insects easily visible. The team advised NASA to let the grass grow long to give the birds the impression that food was hard to catch. (58)
Other, less subtle strategies were implemented to ensure that the birds didn’t settle in. Deterred by plastic owls and floating balloons, alternatively, the flickers soon left for new territory. Their visit to the launchpad, however, was not soon forgotten. Discovery’s successful launch was delayed five weeks while workers flocked to repair the fuel tank the flickers had favored.
49.
Answer and Explanation
Your Answer is
Correct Answer is A
Explanation
Only A matches the subject and verb singular and plural.