The author regards the new means of water-use reduction under discussion as

A． most North Americans would be unlikely to shift their diets simply in order to accommodate the exigencies of water conservation
B． the gains provided by diets with less water-intensive production would likely be less useful in areas with greater aquifer resources
C． people in Asia and certain European countries are dependent on meat-products and could not do without them
D． diets with less water-intensive production tend to be less healthy than those with more water-intense production
E． governments of certain countries would be unlikely to promote programs for diet change given their possible negative effect on those countries' economies

A． Although the future of optical computing is impressive, its applications are too limited in scope to justify much optimism.
B． The outlook of its development is positive on the surface, but many claims made about it are misleading.
C． Efforts to develop the technology have been sufficiently positive to maintain the interest of electrical engineers and physicists.
D． Because of design flaws, the task of developing optical computing will require greater resources than are presently available.
E． The state of development of optical computing is too contradictory to allow for an easy assessment of its future.