The dates that archaeologists assign to most of the colossal sculptures of human heads produced by the Olmec civilization of Mesoamerica are necessarily _____. The majority of the sculptures have been moved from their original context, making precise dating impossible.

Which choice completes the text with the most logical and precise word or phrase?

Although oil shocks-such as the 10% rise in oil prices in November 1970-can strongly affect individual consumers, Gbadebo Oladosu and colleagues have shown that at the level of national economies, their effects are often quite______blank. The effect of recent oil shocks on the gross domestic product of Germany, for example, was only slightly greater than zero.

Which choice completes the text with the most logical and precise word or phrase?

_____ traditional descriptions of pollination syndromes (suites of floral traits, such as pistil length and flower size, hypothesized to have independently evolved as a result of selection pressure exerted by pollinators) and recent empirical observations of floral-trait combinations have led some ecologists to express reservations about the utility of those descriptions.

Which choice completes the text with the most logical and precise word or phrase?

Scientists discovered a 390-million-year-old fossilized forest of Calamophyton trees in modern-day England. The scientists believe the emergence of these Calamophyton forests changed the land significantly. For example, the tree roots would have greatly reduced soil erosion, and the accumulated twigs the trees shed likely created new habitats for animal life.

Which choice best describes the function of the underlined sentence in the text as a whole?

The following text is from Louise Erdrich’s 1986 novel The Beet Queen. The narrator discusses her relationship with her young niece, Dot. Celestine, the narrator’s sister-in-law, is Dot’s mother.

Dot and I had a mental connection, I was sure of it. I understood things about the baby that her mother could not accept.
For instance, she was never meant to be a baby.
Dot was as impatient with babyhood as I. She tried at once to grow out of it. Celestine never saw that, because she, and only she, took pleasure in Dot’s helpless softness. Only Celestine was saddened by her daughter’s fierce progress.
Day by day, Dot grew stronger. In her shopping-cart stroller she exercised to exhaustion, bouncing for hours to develop her leg muscles.

Which choice best describes the main purpose of the text?