Mrs. Kim Dung began to teach English at Tran Cao Van High School 25 years ago.
A. Mrs. Kim Dung has begun to teach English at Tran Cao Van High School for 25 years.
B. Mrs. Kim Dung has taught English at Tran Cao Van High School 25 years ago.
C. Mrs. Kim Dung has been teaching English at Tran Cao Van High School for 25 years.
D. Mrs. Kim Dung has been beginning teaching English at Tran Cao Van High School for 25 years.