请选择DCBA0e*[;Y-E4F9V,{-g5A;E4}(c9f)J Helping others can make us ______ very happy.)c8h/D4s:G)b7q7`.w
A. to feel)c8h/D4s:G)b7q7`.w
B. feeling)c8h/D4s:G)b7q7`.w
C. felt)c8h/D4s:G)b7q7`.w
D. feel)c8h/D4s:G)b7q7`.w