True or False: An aircraft part can be demagnetized by subjecting it to a magnetizing force from alternating current that is gradually reduced in strength.

The statement is true because an aircraft part can indeed be demagnetized using a technique involving alternating current (AC). When an object is exposed to an alternating magnetic field, the direction of the magnetic field continually changes, causing the magnetic domains within the material to experience a sort of back-and-forth motion. As the strength of the AC magnetic field is gradually reduced, the magnetic domains have the opportunity to randomly align rather than maintaining a strong magnetic alignment. This process effectively demagnetizes the part.

Using AC is one of the recognized methods for demagnetization because it facilitates the disorder of the magnetic domains in a controlled manner. Therefore, it leads to a gradual reduction in magnetism, ultimately ensuring that the part becomes demagnetized, which is particularly important in the context of aircraft components to prevent potential issues related to magnetism during operation.

Other options suggest either incorrect methods for demagnetization or conditions that do not align with the principles of magnetic behavior in materials.