In a scalene triangle, all the sides and angles are unequal.
Option 1: Two of the angles of x
o, x
o, 3x
o are same which means that the triangle formed by these angles is isosceles triangle and not scalene.
Option 2 : All the angles

are different which means that the triangle formed by these angles is scalene triangle.
Option 3: All the angles (2x
o, 2x
o, 2x
o) are same which means that the triangle formed by these angles is equilateral triangle and not scalene.
Option 4: Here, the angles (x + 10)
o, (100 - 2x)
o and (x - 40)
o are looking different but if we take (x - 40) = (100 - 2x), then x = (140/3)
o, for which two of the angles become equal and the triangle will become isosceles triangle.
Therefore, Option 2 is correct.