According to the passage, present-day columnar cacti in the Sonoran Desert differ from their close relatives in southern Mexico in that the Sonoran cacti

According to the passage, which of the following types of nectar-feeding pollinators is likely to be an unreliable pollinator of a particular cactus flower?

The primary purpose of the passage is to

Which of the following can be inferred from the passage concerning the environmentalists mentioned in the highlighted text?

According to the passage, Daily sees monetization as an indication of which of the following?

Which of the following most clearly represents an example of an “ecological service” as that term is used in line 20?

Information in the passage suggests that David Pearce would most readily endorse which of  the following statements concerning monetization?

According to the passage, Tucci and Talaga found that service guarantees, when offered by lower-priced restaurants, can have which of the following effects?

It can be inferred that the author of the passage would agree with which of the following statements about the appeal of service guarantees to customers?

The primary purpose of the passage is to