12. The clock in car A is inaccurate, but it can run at a constant speed. One day, when A started shopping, he noticed that both the car clock and his watch (which is accurate) were at 12:00. When he finished shopping, his watch showed 12:30, and the car clock showed 12:35. Later that day, he lost his watch and looked at his car clock, which showed 7:00. What is the actual time?
(A) 5:50
(B) 6:00
(C) 6:30
(D) 6:55
(E) 8:10
12. B.

From the problem, we know that the clock in the car runs 35 minutes for every 30 minutes, indicating that the clock time is $\frac{7}{6}$ times the actual time. Therefore, when the clock shows 7 hours, only 6 hours have actually passed. Thus, the actual time is 6:00.