He has been talented at designing and creating things he was young.
A. when
B. before
C. since
D. while
网友回答
A. when
B. before
(答案→)C. since
D. while
解析：考查连词：A. when当…时候，B. before在…前面，C. since自从，D. while虽然，句意：从小时候他一直很擅长设计和创造东西。因为和现在完成时连用，用since引导时间状语从句，选C。