huffmann codes areSelect one:a. uniquely decodableb. lossless source coding techniquec. all of themd. variable length codes

Huffman codes are all of the above. So, the answer is c. all of them.

Here's why:

a. Uniquely decodable: Huffman codes are designed so that there is a unique way to decode the encoded message. This means that the original message can be perfectly reconstructed from the encoded message.

b. Lossless source coding technique: Huffman coding is a lossless data compression algorithm. This means that when the data is compressed using Huffman coding, no information is lost.

d. Variable length codes: Huffman codes are variable length codes. This means that the length of the code words (the strings of bits used to represent the symbols in the original message) can vary. The most frequently occurring symbols are represented with shorter code words, while less frequent symbols are represented with longer code words. This is what allows Huffman coding to compress data effectively.