5. 다음 밑줄 친 말 중 나머지 넷과 성격이 다른 하나는? (1점) [2005년 3월 대전시]

King Sejong created ①an easily learnable alphabet. However, not everyone accepted Hangul immediately. In those days scholars learned ②the alphabet borrowed from a neighboring country. They disliked the new alphabet. They referred to it as “morning letters” because ③the alphabet could be learned in a single morning. Sometimes they called it ④“women letters” because, at that time, only males could be scholars. For centuries, Hangul was mainly used by people of lower social status. Today, however, it became the most ⑤popular letter in Korea.
제가 보기엔 1번이 답인것 같은데,

답에는 2번입니다.
1번이 한글이고, 5번도 한글인데...

2,3,4번은 다른나라에서 가져온 글 아닌가요? ㅠㅠ