Explanation: In International Morse code, the fundamental unit of time for all elements is the length of a dot (often called a "dit"). A dash (often called a "dah") is defined as being three times the duration of a single dot. This precise 3:1 ratio is a cornerstone of the code's design, ensuring that signals are consistently distinguishable and decodable across different transmission speeds and operators. Therefore, option C is correct: Dashes are about three times as long as dots. Options A and B propose incorrect ratios that would fundamentally alter the code's structure, making it unintelligible. The strict adherence to these timing standards allows for accurate and reliable communication using Morse code, a vital skill in amateur radio.