The numbers are consecutive, meaning they are in arithmetic progression.
Sum of Arithmetic Progression = (n/2)[2a + (n- 1)d]
Where, n = total number of numbers and d = common difference between two successive numbers
Therefore n = 4 and d = 1 ( as the numbers are consecutive )
now (4/2)(2a + (4 - 1)1) = 2
i.e. 2(2a + 3) = 2
i.e. 4a + 6 = 2
i.e. 4a = - 4
i.e. a = - 1
Therefore nos are -1, -1+1 , -1+1+1 , -1+1+1+1
i.e. -1, 0 , 1 , 2
Hope this helps..!!
Thank you :)