87. Kolb’s experiential learning model is suggested to be used in STEM teaching for notonly equipping students with traditional skills in using technology tools but alsopromoting their level of cognition. As the first step begins with hands-on workproviding concrete experience, then the third step is abstraction. The purpose ofabstraction is to build up                   .
(A)hands-on skills
(B)concept
(C)STEM tools, for example, arduino
(D)computing thinking