【单选题】

In most corners of the world malnutrition is plainly a matter of outright insufficiency of food for the population--where the majority of the people do not obtain enough food calories to meet minimal needs for support of physical work and for maintenance of health.Elsewhere the problem may be not one of insufficient, calories but of lack of specific nutrients essential for health.

In LatinAmerica, as in other places, the dread protein deficiency disease kwashiorkor is taking its heavy toll of children’s lives. Strategic vitamins and minerals may be lacking due to traditional diets which are nutritionally imbalanceD、Here people continue their eating pattern year after year without knowledge of that their dietary habits are doing to themselves and to future generations.
With a basic knowledge of nutritional needs and deficiencies, efforts could be directed to finding food substitutes which could meet these needs. Mixtures of vegetable proteins, like soybeans and peanuts, could provide an abundance of cheap, useful protein where meat, eggs, and milk are not within economic reach of large groups in the population.Efforts could also be expended on increasing the agricultural productivity in specific regions; where large areas are given over to relatively inefficient use as grazing land, the intensive production of vegetable protein crops could bring remedial nutrition to an undernourished population.Elsewhere, enrichment with specific vitamins and minerals of traditional staple foods that are deficient in essential nutritive factors could wipe out disabling deficiency diseases, like beriberi or pellagra, almost overnight. Similarly, addition of minute amounts of inexpensive iodine to salt could benefit large areas where endemic goiter has been accepted as an integral part of life for generations.
Cheap protein substitutes for milk, eggs, and meat ______.A．may be obtained from vitamins and minerals
B．are being sought by scientists
C．can be gotten from soybeans
D．can be found in iodized salt