______in the past, at the moment it is a favorite choice for wedding gown.

A. Unpopular has as white been

B. White has been as unpopular
C. Unpopular has been as white

D. Unpopular as white has been

“最优化”是教学设计的核心问题，最优化即是（）

A、理想化

B、所有条件下的最佳

C、教师在给定条件下努力达到最优的教学效果

D、在原有的基础上，通过师生的努力，有所进步