题目内容：

Imagine a town with crosswalks but no pedestrians, cars and trucks but no drivers. Welcome to Mcity, a fake “city” built by researchers who are testing out the driverless cars of the future.

The controlled test environment, which opened today (July 20, 2015) at the University of Michigan in Ann Arbor, covers 32 acres (the size of about 24 football fields) and contains all the trappings of a real suburb or small city. There is an entire network of roads lined with sidewalks, streetlights, stop signs and traffic signals. There’s even a “downtown” area complete with fake buildings and outdoor dining areas.

The idea behind Mcity is simple: test out new driverless car innovations in a human-free environment before these technologies are unleashed in the real world.

"Mcity is a safe, controlled, and realistic environment where we are going to figure out how the incredible potential of connected and automated vehicles can be realized quickly, efficiently and safely," Peter Sweatman, director of the Mobility Transformation Center at U-M, said in a statement.

The roads of Mcity are built to stand up to “rigorous, repeatable” testing, according to MTC officials. While Mcity drivers don't have to compete with real pedestrians, there will be one mechanical foot-traveler (a robot-like machine named Sebastian) that steps out into traffic to see whether the automated cars can hit the brakes in time. The fake city also features a traffic circle, a bridge, a tunnel, some unpaved roads, and even a four-lane highway with entrance and exit ramps, according to a report by Bloomberg Business.

In addition to evaluating fully automated, or driverless cars, the researchers also hope to test out so-called connected vehicles within Mcity’s limits. Connected cars can either communicate with one another (vehicle-to-vehicle control, or V2V) or with pieces of equipment, such as traffic lights, that are located near roadways (vehicle-to-infrastructure control, or V2I).

Even the smallest details of Mcity have been planned out in advance to copy the conditions that connected and automated vehicles could face in the real world. For example, there are street signs covered up with graffiti, and faded yellow and white lane markings line the streets.

Mcity is just one part of a much larger project that MTC and its partner organizations are establishing in an effort to get a whole fleet of connected and driverless cars on the road in Ann Arbor by 2021. In addition to the fake city, MTC is also continuing to launch connected and semi-autonomous(半自动) cars on real roadways. Eventually, the University of Michigan and the Michigan Department of Transportation said they hope to put 20,000 connected cars on the roads of southern Michigan.

1.According to the passage, Mcity ________.

A. is a real town used to evaluate the function of future cars

B. is a fake city with transportation system but no pedestrians

C. covers an area of 32 acres with as many as 24 football fields

D. owns a downtown area with a bridge and some unpaved roads

2.Why did researchers build Mcity?

A. To test new driverless cars.

B. To make a real suburb or small city.

C. To control road environment.

D. To build an entire network of roads.

3.It can be inferred from the passage that ________.

A. some connected and semi-autonomous cars have been put into use

B. the researchers plans to create a robot-like machine to direct the traffic

C. the widespread use of driverless cars will soon come into reality in America

D. MTC is attempting to make connected and driverless cars available on real roads

4.How does the passage mainly develop?

A. By presenting descriptions of the design.

B. By describing a cause and its effects.

C. By providing the time order.

D. By comparing the opinions.