question: What does the Kraft inequality state for any instantaneous code over an alphabet of size D? option 1: The sum of codeword lengths must be greater than or equal to D. option 2: The sum of codeword lengths must be less than or equal to D. option 3: The difference between the longest and shortest codeword lengths must be less than or equal to D. option 4: The product of codeword lengths must be equal to D. 