題目：
Only after hearing about a potential job promotion did she begin
working ____________ than the other employees.
(A) efficiently
(B) more efficiently
(C) efficient
(D) more efficient
疑問：答案(B) 我選(D) 選D的原因是念起來順而且形容詞也常出現
不懂這題為什麼選副詞,請問如何判別,麻煩大大賜教\