All of the Following Statements Are True EXCEPT

All of the following statements are true EXCEPT:

A) magnaflux is the common trade name for a more sophisticated type of magnetic crack detection.
B) heads that are especially susceptible to cracks are often inspected by pressure testing
C) crack inspection on iron heads can be performed using a simple magnetic crack detector.
D) removal of 0.020" from OHC head surfaces results in about 10 degrees of retard in valve timing.