Read the contour map of a place along the eastern coast of China and complete the following questions. (1) If a road is built between Village A and Village B, you should choose _ _ _ _ _.

(1) According to the contour topographic map, among the ② and ③ lines in the highway construction from Village A to Village B, ② line should be selected, because the slope of ② line is small and the engineering quantity is small.

(2) As can be seen from the contour topographic map, Zhong Ding Village in villages A, B, C and D is flat and open, with convenient land and water transportation, and the most favorable conditions for developing towns.

(3) From the contour topographic map, ④ is located at the narrowest exit of the basin. If a hydropower dam is built here, the amount of work is small and the reservoir capacity is large. However, the following problem will be that the reservoir will flood villages and farmland and require resettlement.

So the answer is: (1) ②; Small slope and small engineering quantity; (2) Ding Cun; Ding Cun is flat and open, with convenient land and water transportation; (3) (4) Located at the narrowest outlet of the basin, the project quantity is small and the reservoir capacity is large; Flooding villages and farmland requires immigration and other problems.