If we want to show that there is a problem against a certain research background, we can use
选项：

A:(Problems in certain research area) are …, yet (the present solution) has frequently been questioned because …;
B:This paper describes/presents … (the argument) within … (a theoretical context);
C:Based on the idea that …, we conducted the present study, categorized …, and evaluated …;
D:While (the debate on certain research subject) seems to …, (the present agreement) is still problematic.