Flux density is a measure of the number of magnetic flux lines perpendicular to an area of cross-section. If a discontinuity is in the plane of the unit area, the strongest magnetic article indication will be formed when the discontinuity is:

• A. Inclined at 45º to the flux lines
• B. Parallel to the flux lines
• C. 90º to the flux lines
• D. 135º to the flux lines