根据以下材料回答 1～20 题： Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1. (10 points) Research on animal intelligence always makes me wonder just how smart humans are___(1)___the fruit-fly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly __(2)__to live shorter lives. This suggests that __(3)___ bulbs burn longer, that there is a(n)___(4)___in not being too terrifically bright. Intelligence, it ____(5)_ , is a highpriced option. It takes more upkeep, burns more fuel and is slow___(6)___ the starting line because it depends on learning—a (an) ____(7)_ process—instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to __(8)____. Is there an adaptive value to __(9)___intelligence? That’s the question behind this new research. I like it. Instead of casting a wistful glance__(10)____at all the species we’ve left in the dust I.Q.wise, it implicitly asks what the real____(11)__of our own intelligence might be. This is__(12)___the mind of every animal we’ve ever met. Research on animal intelligence also makes me wonder what experiments animals would__(13)___on humans if they had the chance. Every cat with an owner, ___(14)___, is running a small-scale study in operant conditioning. We believe that__(15)____animals ran the labs, they would test us to___(16)___the limits of our patience, our faithfulness, our memory for terrain. They would try to decide what intelligence in humans is really__(17)__, not merely how much of it there is.__(18)___, they would hope to study a__(19)__question: Are humans actually aware of the world they live in?__(20)____the results are inconclusive. 第 1 题 请选择(1)处最佳答案（ ）。