What type of file compression retains all original data?

Lossless compression is the correct answer because it allows all the original data to be perfectly reconstructed from the compressed data. This means that no information is lost during the compression process, making it ideal for applications where preserving the exact quality and details of the original file is crucial. This type of compression is often used for text documents, software files, and certain image formats, where any loss of data could compromise functionality or quality.

In contrast, lossy compression reduces file size by permanently eliminating some data, especially in media formats like audio, video, and images, where a degree of quality loss may be acceptable. TekCompression and Adaptive Compression do not refer to widely recognized or established methods for general file compression, thus making them less relevant in this context. Lossless compression stands out as the method that ensures data integrity, making it the appropriate choice for scenarios requiring complete data retention.