Ecologist: Smallpox, one of the worst diseases ever to afflict humans, has in some outbreaks killed as much as 50 percent of local populations. The last known surviving cultures of variola—the smallpox virus—are confined to two high-security laboratories. Some scientists are anxious to destroy the remaining variola cultures, to which humans are susceptible. Research on the cultures, however, may someday lead to important benefits for humans, and so the cultures should not be destroyed.
Which one of the following, if true, would do most to strengthen the ecologist’s argument?
(A) Smallpox has killed millions of humans over the centuries, and when it reaches the stage of an epidemic it is extremely difficult to eradicate.
(B) It is more likely that the virus, if left available to researchers, will lead to an important medical breakthrough than that the virus will be accidentally released from the laboratory.
(C) Variola is a rare type of virus in that it can only be transmitted from one human to another, yet does not affect rats, monkeys, or insects.
(D) It is becoming increasingly important to prevent any nation from acquiring the means to wage biological warfare.
(E) It is likely that the virus, if released, will develop a resistance to vaccines previously used to control it.
Conclusion - "Research on the cultures, however, may someday lead to important benefits for humans, and so the cultures should not be destroyed"
Now we need to find the option that says - Yes if we preserve the virus it will lead to important benefits
See how option B clearly strenthens the argument - important medical breakthrough will definately benefit humans
No other is even close to the contending answer that's why all other options are easy to eliminate