Question ID:PT92 S3 Q7 Passage:Because most agricultural practices in North America produce row after row of only a few, genetically identical, varieties of crops, the continent's food system rests precariously on a rapidly eroding genetic base, increasingly susceptible to pests and disease. As a possible solution, agricultural researchers, development experts, and policy makers are searching for ways to conserve the wealth of genetic information contained in crops known as heirloom varieties, which have been developed and maintained by indigenous farmers for many generations. The store of agricultural knowledge associated with the cultivation of these varieties has only recently been recognized as a valuable resource by crop geneticists, who have tended to base their research and their thinking solely on agricultural methods brought to North America from elsewhere. But given the intensity with which these non‚ North American methods seek to maximize the land's output for economic reasons, they are not always suited to preserving a diverse pool of crop genetics.A recent study describes how generations of indigenous farmers relied on their understanding of practical genetics to develop hundreds of varieties of each indigenous plant cultivated. For example, long aware of the technique referred to now as hybridization, indigenous farmers frequently used the pollen from one variety of corn to fertilize another variety, thereby creating many varieties of sweet corn, dent or cereal corn, popcorn, and numerous other types. This variation allowed for the exploitation of the crops' natural ability to resist pests and disease. Furthermore, indigenous farmers maintained those varieties that provided the best yields in their local environment; varieties in the wet areas along the coastal plains, for instance, differed substantially from those grown in the mountains. Thus in addition to being more resistant to pests and disease, heirloom crops are less dependent on intensive irrigation systems because they have been selectively bred for particular environments.Many of these heirloom varieties are preserved in household seed stocks by indigenous farmers who obtain seeds through long-standing family, community, and regional exchange networks; similarly, knowledge of the required development and cultivation methods has been maintained through the centuries by intergenerational exchanges within an oral tradition. Over the past century, however, penetration of the world market economy into small agricultural communities, both native and non-native, has discouraged small-scale, internal food production in favor of income-generating work. The result has been a dwindling number of small farmers‚ with many of those planting nonheirloom, commercial seed varieties‚ and a breakdown of many community and regional exchange networks. These recent developments have made clear that immediate steps must be taken to preserve indigenous knowledge systems and integrate them with programs for the conservation of diverse crop genetics, thus bolstering the long-term sustainability of the continent's agricultural systems. Stem:The author would be most likely to agree with which one of the following statements about the crop geneticists mentioned in the second-to-last sentence of the first paragraph? Correct Answer Choice:AChoice A:They have been too willing to further intense efforts to maximize the land's agricultural output. Choice B:They are focused on maximizing crop production at the expense of small farmers. Choice C:They have not demonstrated any interest in diversifying the crop genetic pool. Choice D:They are interested in heirloom crop varieties because they help maximize specific crop yields. Choice E:They continue to ignore heirloom crop varieties in favor of commercial varieties.