[单选题]
A system consists of 3.0 kg of water at4eu 3( udvkmf.l kn8oh(p yya lugg:w6 s(30l; $80 ^{\circ}C$. 30 J of work is done on the system by stirring with a paddle wheel, while 66 J of heat is removed. What is the change in internal energy of the system?
A. $36 \; J$
B. $-36 \; J$
C. $96 \; J$
D. $-96 \; J$