[has been established by c...] The period when the great painted caves at Lascaux and Altamira were occupied by Upper Paleolithic p

For Competitive Exams

The period when the great painted caves at Lascaux and Altamira were occupied by Upper Paleolithic people has been established by carbon-14 dating, but what is much more difficult to determine are the reason for their decoration, the use to which primitive people put the caves, and the meaning of the magnificently depicted animals.

has been established by carbon-14 dating, but what is much more difficult to determine are

has been established by carbon-14 dating, but what is much more difficult to determine is

have been established by carbon-14 dating, but what is much more difficult to determine is

have been established by carbon-14 dating, but what is much more difficult to determine are

are established by carbon-14 dating, but that which is much more difficult to determine is

Explanation:
Two instances of subject-verb agreement must be observed in this sentence: The period ... has been established and what is much more difficult to determine ... is. Both clauses have singular subjects and must have singular verbs. Only B, the best choice, observes these requirements. A incorrectly uses the plural form are in the second clause. Choices C and D incorrectly use the plural form have in the first clause, and D incorrectly uses are in the second clause as well. E incorrectly uses the plural form are in the first clause. Furthermore, because the date of the period in question was established before the writing of the sentence, the verb of that clause must be in the present perfect form (has been established).

Additional Questions

The Baldrick Manufacturing Company has for several years followed a policy aimed at decreasing operating costs and improving the efficiency of its distribution system.	Answer
Parliament did not accord full refugee benefits to twelve of the recent immigrants because it believed that to do it rewards them for entering the country illegally.	Answer
Many policy experts say that shifting a portion of health-benefit costs back to the workers helps to control the employer s costs, but also helps to limit medical spending by making patients more careful consumers.	Answer
The Federalist papers, a strong defense of the United States Constitution and important as a body of work in political science as well represents the handiwork of three different authors.	Answer
More and more holidaymakers are choosing to fly to remote islands in search of the perfect beach; seeking sand, sun and palm trees, rather than centers of entertainment.	Answer
The plot of The Bostonians centers on the rivalry between Olive Chancellor, an active feminist, with her charming and cynical cousin. Basil Ransom, when they find themselves drawn to the same radiant young woman whose talent for public speaking has won her an ardent following.	Answer
Ricks has written extensively on not only major figures in English poetry like Milton and Housman, but also on the lyrics of Bob Dylan.	Answer
The government requires that these forms should be submitted before the end of the financial year.	Answer
The mole is a nocturnal insectivorous mammal regarded as pests by gardeners because of their burrowing activity spoiling lawns and gardens.	Answer
Often said to be the most perfectly cut of all large diamonds, the Jubilee`s facets are so exact that it can be balanced on its culet, which is less than two millimeters across.	Answer

Share with Friends