At what week is the fingerprint completely developed?

The fingerprints are fully developed by around 24 weeks of gestation. During fetal development, the formation of fingerprints, or dermal papillae, begins early in pregnancy, but it is at around 24 weeks that the patterns become distinct and stable. This development occurs due to the interplay of genetic and environmental factors and is influenced by the intrauterine conditions.

Before 24 weeks, while some features of fingerprints may be present, they are not yet fully formed or recognizable as unique patterns. This is why the other options, such as 20 weeks, 22 weeks, and 26 weeks, do not reflect the correct timeline for complete fingerprint development. After 24 weeks, while the fingerprints remain unchanged, they continue to grow in size proportionate to the rest of the body. Hence, the accurate answer is centered around the 24-week mark in fetal development.