The Antietam campaign of 1862 was the occasion for two attempts of the Confederate army to destroy the Monocacy Aqueduct but soldiers were unable to drill enough holes into the hard stone to place explosives that would breach the aqueduct.

(A) The Antietam campaign of 1862 was the occasion for two attempts of the Confederate army to destroy the Monocacy Aqueduct but soldiers were unable to drill enough holes into the hard stone to place explosives that would breach the aqueduct.

(B) Soldiers were twice unable to drill enough holes into the hard stone of the Monocacy Aqueduct to place enough explosives to breach it during the 1862 Antietam campaign of the Confederate army.

(C) The Confederate army twice attempted to destroy the Monocacy Aqueduct during the 1862 Antietam campaign but soldiers were unable to drill enough holes into the hard stone to place enough explosives to breach the aqueduct.

(D) The hard stone of the Monocacy Aqueduct made it twice impossible to drill sufficient holes during the Confederate army's 1862 Antietam campaign for soldiers to place enough explosives to breach the aqueduct.

(E) The Monocacy Aqueduct was twice attempted to be breached during 1862's Antietam campaign but soldiers were unable to drill enough holes into the hard stone to place enough explosives to destroy the aqueduct.

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From 1970 to 1990, sea otters made up a steadily decreasing percentage of the marine life population in North America. The increasingly widespread effects of pollution and habitat destruction were responsible for this decrease. However, although pollution was a more frequent target of environmental legislation, it was found that pollution in North America increased by a greater percentage than did the rate of habitat destruction.

Which of the following, if true, most helps to account for the finding?

(A) Environmental legislation limiting industrial pollution was much more financial onerous on North American firms than legislation protecting marine habitats.

(B) The decreasing percentage of sea otters among the marine population had a positive effect on the species that sea otters typically prey on.

(C) Most of the habitats likely to be destroyed by human activity had already been compromised for marine life by 1970.

(D) Habitat destruction was a more frequent target of environmental legislation than pollution in the decade preceding 1960.

(E) Marine life as a whole was more significantly affected by pollution than by habitat destruction.

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Contrary to common belief, Euclid's Elements is more a compilation than a composition; it repeats the work of scholars such as Eudoxus, Pythagorus, and Theaetetus, often clarifying earlier proofs and correcting weak ones.

(A) Contrary to common belief, Euclid's Elements is more a compilation than a composition; it repeats the work of scholars such as Eudoxus, Pythagorus, and Theaetetus, often clarifying earlier proofs and correcting weak ones.

(B) Contrary to common belief, Euclid's Elements is more a compilation than a composition, repeating work by scholars such as Eudoxus, Pythagorus, and Theaetetus, who clarified earlier proofs and corrected weak ones.

(C) Contrary to common belief, Euclid's Elements is more compilation than composition that repeats the work of Eudoxus, Pythagorus, and Theaetetus, accomplished by clarifying and correcting earlier and weak proofs.

(D) Euclid's Elements, contrary to common belief, is more a compilation than a composition; repeating the work of scholars such as Eudoxus, Pythagorus, and Theaetetus; it often clarifies earlier proofs and corrects weak ones.

(E) Euclid's Elements is more a compilation than a composition; contrary to common belief, the work of scholars such as Eudoxus, Pythagorus, and Theaetetus are repeated by it, which clarifies earlier proofs and corrects weak ones.

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Geraflex, a new exercise program designed to strengthen muscle in the elderly, is offered year-round, and a typical class contains between five and ten members, most of whom already suffer from age-related muscle loss. Classes are generally larger from April through October; from November through March, class sizes tend to be smaller. The variation in class size can probably be explained by a decrease in mobility among the elderly during the winter months.

Which of the following, if true, provides the strongest support for the explanation offered?

(A) From April to October, more Geraflex classes are offered than from November to March.

(B) Geraflex class sizes vary dramatically in size from year to year.

(C) Many elderly people travel to warmer climates during the winter months.

(D) An effective muscle strengthening program requires much more extensive stretching in the colder winter months.

(E) During the winter months in many areas, roads and sidewalks are more dangerous, so the elderly are less likely to leave their homes.

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