1. 


A. 1 and 2 only
B. 2 and 3 only
C. 1, 2, 3 and 4
D. 2 and 4 only

Answer: Option C

Explanation:

The shaded side is adjacent to the side with dot. In picture (1) it is clearly shown. In figures (2), (3) and (4) it is possible to have both the sides with dot and shade adjacent to each other. So option (C) is the correct answer.