请选择DCBA)[5T)[,f5B;q4z1I,k Helping others can make us ______ very happy..o)^+E0`2D
A. to feel.o)^+E0`2D
B. feeling.o)^+E0`2D
C. felt.o)^+E0`2D
D. feel.o)^+E0`2D