What are hand-held scan tools and what are they used for? 1- Hand-held scan tools are the most powerful and versatile tools for diagnosing the eng...

What are hand-held scan tools and what are they used for?

1- Hand-held scan tools are the most powerful and versatile tools for diagnosing the engine management systems on modern cars.
2- OBD stands for On-Board Diagnostics and is essentially a load of sensors feeding information to a computer.
3- OBD cars started appearing in the early 1990s.
4- OBD-ll is a much more sophisticated system that was introduced in the mid-1990s.
a) Only 1 and 2 are correct.
b) Only 2 and 3 are correct.
c) Only 1, 2, and 3 are correct.
d) 1, 2, 3, and 4 are correct.