The only patterns usually used to define pattern areas for classification purposes are...

• A. Loops and Whorls
• B. Arches and Loops
• C. Arches and Whorls
• D. Circles and Lines

Answer: (A)

In fingerprint classification, the pattern areas are defined by features that provide clear landmarks on each finger. Loops and whorls both have distinct landmarks like cores and deltas that let classifiers reliably group patterns into major categories. Arches, while a valid pattern type, lack these landmark features (no delta and often no pronounced core) and are not used to define the standard pattern areas for classification. So the patterns typically used to define pattern areas are loops and whorls.