Do you scream on a roller coaster ride? You slowly climb up a steep slope until an almost vertical(垂直的) drop, and then... Ahhhhhhhh! Thrill-seekers like me are in luck because theme parks are pushing the boundaries of technology to create the fastest, tallest, scariest roller coasters the world has ever known.
Alton Towers in Britain opened the world's first 14-1oop roller coaster a few months ago, called The Smiler. Over in Abu Dhabi, Ferrari World claims to have the world's fastest one. Ferrari World's Formula Rossa ride sends out passengers from 0-240km/h in just 4. 9 seconds. During this rapid acceleration they experience G-forces only fighter pilots usually  feel: Up to 4. 8G. The designer of several rides at Alton Towers, said: "While we can stand 6-8Gs for very short periods of  time, ff we experience 5G for more than five seconds we're likely to "black out."
On modern roller coasters passengers experience about 3G in tight turns and loops. But while we may have reached the limit in terms of G-forces, there is no technological limit to how fast or how high roller coasters can go---it's all down to money. Alton Towers' The Smiler cost ~18m to build.
Some companies are finding other ways to keep us amused. There's a move towards indoor rides where the experience is improved by audio-visual technologies. For example, a company called Dynamic Structures is currently developing a "coal-mine-themed" ride for a client in Dubai that will combine speed and G-forces with 3D projection effects and robotics, which will trick your brain into thinking you're really falling.
I can't wait to enjoy this one. What about you: Do you like being upside down?
The underlined phrase "black out" in the second paragraph probably means  ....  .

A．stop breathing	B．lose consciousness for a short time
C．lose memory forever	D．bleed to death

We can learn from the passage that __

A．all the theme parks are creating the fast roller coasters

B．the Smiler sends out passengers from 0-240km/h in just 4.9 seconds

C．it is unusual for fighter pilots to feel up to 4.8G

D．the more the money is spent, the faster the roller coaster can go

The feature of the "coal-mine-themed" ride is

A．3Dtechnologies

B．indoor rides

C．G-forces

D．dynamic structures

What is the best title for the passage?

A．The Fastest Roller Coaster	B．The Smiler and G-forces
C．Screaming for Fun	D．The New Technology