After A.A.t3, systems A and B are in equilibrium, the equilibrium state of the two systems is the same, and the volume fraction of C is the same, so A is wrong;
B. The positive and negative reactions should be exothermic. When the temperature balance increases, it moves in the reverse reaction direction, and the conversion rate of A decreases, which is inconsistent with the image, so B is wrong;
At the moment of C. t 1, the system of curves A and B has not reached the equilibrium state and the reaction is going on, so VA (positive): VC (inverse) > 2: 3, that is, 3VA (positive) > 2VC (inverse), so C is correct;
D, at constant temperature, the volume of the reaction container decreases, the pressure increases, the reaction rate is accelerated, and the time to reach equilibrium is shortened, and the reaction is a reaction with constant gas volume.
The balance does not move, so reducing the volume can change curve B into curve A, so D is wrong.
So choose C.