33. 如圖(十)所示之 OPA 電路,在何種情況下,輸出電壓為負值?(A) V₁=0.1V,V₂=-0.1V(B) V₁=0,V₂=-0.1V(C) V₁=0.1V,V₂=0.2V(D) V₁=-0.1V,V₂=-0.2V