Final answer:
The statement about the necessity of drilling to remove a broken bolt is false, as there are other methods such as using a bolt extractor. Option B is correct.
Step-by-step explanation:
The statement 'The only way to remove a broken bolt is to drill it out' is false. There are multiple methods to remove a broken bolt, not just drilling. For example, one can use a bolt extractor, apply heat to expand the metal and loosen the bolt, or even use chemicals to dissolve corrosion that may be binding the bolt.
Now, addressing the concept related to mechanics, when they put a length of pipe over the handle of a wrench to remove a very tight bolt, it effectively increases the leverage. This extra leverage allows the mechanic to apply more torque to the bolt with less effort. However, it is indeed hazardous as it can exceed the torque design of the bolt, possibly causing it to break.
Lastly, when you drop a bar magnet through a copper tube, it does induce an electric current in the tube, making the statement true.
Using a pipe over a wrench increases leverage and torque, which can help but also risks breaking the bolt. Dropping a bar magnet through a copper tube induces an electric current, thus the statement is true.