Multiple-choice Choose Single Answer – Read the text and answer the multiple-choice question by selecting the correct response. This item type assesses reading skills. It requires test takers to read, analyze, understand and assess a short text on an academic subject and choose a single correct response.
PTE Practice – Multiple-choice Choose Single Answer
1. Read the passage and answer the following question.
Diamonds, an occasional component of rare igneous rocks called lamproites and kimberlites, have never been dated satisfactorily. However, some diamonds contain minute inclusions of silicate minerals, commonly olivine, pyroxene, and garnet. These minerals can be dated by radioactive decay techniques because of the very small quantities of radioactive trace elements they, in turn, contain. Usually, it is possible to conclude that the inclusions are older than their diamond hosts, but with little indication of the time interval involved. Sometimes, however, the crystal form of the silicate inclusions is observed to resemble more closely the internal structure of diamond than that of other silicate minerals. It is not known how rare this resemblance is, or whether it is most often seen in inclusions of silicates such as garnet, whose crystallography is generally somewhat similar to that of diamond; but when present, the resemblance is regarded as compelling evidence that the diamonds and inclusions are truly cogenetic.
Ques 1. The main purpose of the passage is to
[A]. explain why it has not been possible to determine the age of diamonds.
[B]. explain how it might be possible to date some diamonds.
[C]. compare two alternative approaches to determining the age of diamonds.
[D]. compare a method of dating diamonds with a method used to date certain silicate minerals.
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2. Read the passage and answer the following question.
Since the Hawaiian Islands have never been connected to other land masses, the great variety of plants in Hawaii must be a result of the long-distance dispersal of seeds, a process that requires both a method of transport and an equivalence between the ecology of the source area and that of the recipient area.
There is some dispute about the method of transport involved. Some biologists argue that ocean and air currents are responsible for the transport of plant seeds to Hawaii. Yet the results of flotation experiments and the low temperatures of air currents cast doubt on these hypotheses. More probable is bird transport, either externally, by accidental attachment of the seeds to feathers, or internally, by the swallowing of fruit and subsequent excretion of the seeds. While it is likely that fewer varieties of plant seeds have reached Hawaii externally than internally, more varieties are known to be adapted to external than to internal transport.
Ques 2. The author is primarily concerned with
[A]. discussing different theories about the transport of plant seeds to Hawaii.
[B]. discussing different approaches biologists have taken to testing theories about the distribution of plants in Hawaii.
[C]. discussing the extent to which air currents are responsible for the dispersal of plant seeds to Hawaii.
[D].resolving a dispute about the adaptability of plant seeds to bird transport.
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