請依下文回答第 46 題至第 50 題
        We like music because it makes us feel good. But why does it make us feel good? Neurologists have utilizedmagnetic resonance imaging to show that people listening to pleasurable music had activated brain regions calledthe limbic and paralimbic areas, which are connected to euphoric reward responses, like those we experience fromsex, good food and addictive drugs. Those rewards come from a gush of a neurotransmitter called dopamine.       But why? It’s easy enough to understand why sex and food are rewarded with a dopamine rush: this makes uswant more, and so contributes to our survival and propagation. But why would a sequence of sounds with no obvioussurvival value do the same thing？ The truth is no one knows. However, we now have many clues to why musicprovokes intense emotions. The current favorite theory among scientists who study the cognition of music – howwe process it mentally – dates back to 1956, when the philosopher and composer Leonard Meyer suggested thatemotion in music is all about what we expect, and whether or not we get it. Meyer drew on earlier psychologicaltheories of emotion, which proposed that it arises when we’re unable to satisfy some desire. That creates frustrationor anger – but if we then find what we’re looking for, be it love or a cigarette, the payoff is all the sweeter. This iswhat music does too. It sets up sonic patterns and regularities that tempt us to make unconscious predictions aboutwhat’s coming next. If we’re right, the brain gives itself a little reward – as we’d now see it, a surge of dopamine.The constant dance between expectation and outcome thus enlivens the brain with a pleasurable play of emotions.       Since it’s not as if our life depended on them, why should we care whether our musical expectations are rightor not? Perhaps once it did. Making predictions about our environment – interpreting what we see and hear on thebasis of only partial information – could once have been essential to our survival, and indeed still often is, forexample when crossing the road. And involving the emotions in these expectations could have been a smart idea.On the African savannah, our ancestors did not have the luxury of mulling over whether that screech was made bya harmless monkey or a predatory lion. By bypassing the “logical brain” and taking a shortcut to the primitivelimbic circuits that control our emotions, the mental processing of sound could prompt a rush of adrenalin – a gutreaction – that prepares us to get out of there anyway.We all know that music has this direct line to the emotions.       We can’t turn off this anticipatory instinct, nor itslink to the emotions – even when we know that there’s nothing life-threatening in a Mozart sonata.
【題組】48 Which of the following is closest in meaning to primitive in the passage?
(A) fragmentary.
(B) rudimentary.
(C) supplementary.
(D) complementary.