单项选择题

A．The Vacuum: Its Fluctuations and Decay.B．The Vacuum: ……

Which of the following titles best describes the passage as a whole

A．The Vacuum: Its Fluctuations and Decay.
B．The Vacuum: Its Creation and Instability.
C．The Vacuum: A state of Absence.
D．Particles That materialize in the Vacuum.

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单项选择题It can be inferred from the passage that scientists are currently making efforts to observe which of the following events

A．The decay of a vacuum in the presence of virtual particles.
B．The decay of a vacuum next to a super heavy atomic nucleus.
C．The creation of a superheavy atomic nucleus next to an intense electric field.
D．The creation of a virtual electron and a virtual positron as a result of fluctuations of a vacuum.

单项选择题From the sentence Like Proust, the French author whose experiences became his literary capital, man can recapture the past. you can tell that Proust

A．wrote primarily to improve his future life.
B．discovered thing about his future life.
C．described man's development of time sense.
D．wrote about past experiences.

单项选择题The word contingencies underlined here means

A．uncertainties.
B．dependent conditions.
C．incidental thought.
D．events that may occur.

单项选择题This article is about

A．time sense in animals.
B．how man's time sense separates him from animals.
C．man's preoccupation with past and future events.
D．how apes understand time relationships.

单项选择题According to the article, which of the following statements is TRUE

A．Chimpanzees' sense of time is as good as man's.
B．Man developed from apes.
C．Memory and foresight contribute to intelligence.
D．Monkeys and apes are almost as intelligent as man.