Look!The bird is flying__________ in the sky. Maybe it was injuried. A: unsteady B: unsteadily C: steady D: steadily

Immune defense means that the body can () A: resist to invasion of pathogens and neutralize their toxic products B: exclude the aging and injuried cells and keep the balance of inner<br/>environment C: surveil and clear transformed cells inside the body D: present unresponsive state to antigenic foreign substances E: present unresponsive state to self antigenic