In countries in which new life-sustaining drugs cannot be patented, such drugs are sold at widely affordable prices; those same drugs, where patented, command premium prices because the patents shield patent-holding manufacturers from competitors.  These facts show that future access to new life-sustaining drugs can be improved if the practice of granting patents on newly developed life-sustaining drugs were to be abolished everywhere.

Which of the following, if true, most seriously weakens the argument?

A major impediment to wide acceptance of electric vehicles even on the part of people who use their cars almost exclusively for commuting is the inability to use electric vehicles for occasional extended trips.  In an attempt to make purchasing electric vehicles more attractive to commuters, one electric vehicle producer is planning to offer customers three days free rental of a conventional car for every 1,000 miles that they drive their electric vehicle.

Which of the following, if true, most threatens the plan’s prospects for success?

Archaeologists in Michigan have excavated a Native American camp near Dumaw Creek.  Radiocarbon dating of animal bones found at the site indicates that the camp dates from some time between 1605 and 1755.  However, the camp probably dates to no later than 1630, since no European trade goods were found at the site, and European traders were active in the region from the 1620’s onward.

Which of the following, if true, most strengthens the argument?

A one-million-year-old skull bearing traits associated both with Homo erectus and, in addition, Homo sapiens has been found in the Afar region of Eritrea, and indicates that modern humans developed much earlier than previously thought.

Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.

Automobile emissions are a significant source of air pollutants, and cars over five years old typically generate significantly greater amounts of pollutants than newer cars.  In Torinia, which has recently built its first automobile manufacturing plant, most cars are over five years old.  Aiming to boost Torinia’s economy and reduce air pollution, the government plans to introduce incentives for Torinians to scrap their old cars every five years and replace them with new ones.

Which of the following, if true, most seriously undermines the likelihood that the planned incentives, if implemented, will achieve both of the cited aims?

Parasitic wasps lay their eggs directly into the eggs of various host insects in exactly the right numbers for any suitable size of host egg.  If they laid too many eggs in a host egg, the developing wasp larvae would compete with each other to the death for nutrients and space.  If too few eggs were laid, portions of the host egg would decay, killing the wasp larvae.

Which of the following conclusions can properly be drawn from the information above?

The application of a new method for analyzing the chemistry of tooth enamel allows scientists to examine molars of prehuman ancestors and determining that their diets were more varied than had been supposed.

The continental United States receives an average of 30 inches of precipitation a year; transpiration from soil and from plants returns approximately 21 of the 30 inches to the atmosphere, while the balance of 9 inches contributes to the flow of streams and rivers.

1998 saw several new ventures promoting online distance learning both at the college and graduate level, but also faculty members in large numbers began questioning whether the computer screen was an adequate replacement for the classroom.

Whereas scientists, because of random fluctuations in the weather, cannot determine the transition from one season to the next by monitoring temperatures on a daily basis, so they cannot determine the onset of global warming by monitoring average annual temperatures.

An overly centralized economy, not the changes in the climate, is responsible for the poor agricultural production in Country X since its new government came to power.  Neighboring Country Y has experienced the same climatic conditions, but while agricultural production has been falling in Country X, it has been rising in Country Y.

Which of the following, if true, would most weaken the argument above?

The automobile company announced that the average price of next year’s models would decrease four-tenths of one percent, amounting to about $72, as compared with comparably equipped cars and trucks this year.

Many teenagers undergo stress, but results of a recent study indicate that the patterns of stress that girls experience are more likely to result in depression than are those that boys experience.