How is the number 'one' expressed in Korean?

The number 'one' is expressed in Korean as "Hana." This term originates from the native Korean counting system, which includes unique words for numbers one through ten that differ from the Sino-Korean system, which incorporates Chinese characters. "Hana" is commonly used in various contexts, such as when counting objects or indicating a single item.

The other options represent different numbers or are terms that do not denote 'one.' For example, "Set" is not applicable in this context as it does not correspond to a specific number in Korean. "Yul" is the Korean word for 'ten' in the Sino-Korean counting system, while "Dae" does not correspond to 'one' either and is more closely associated with the concept of 'big' or 'great' in certain contexts. Thus, "Hana" is the correct representation of 'one' in Korean.