Correct Answer:

Solution : Here the pattern is as follows —
1. In the given series, the set of three black triangles and white triangles are moving two places at a time alternately in a clockwise direction.
2. The rotation started from the mid-right corner in a black triangle and in a white triangle this movement started from the top right corner of the triangle.
Thus, the missing part of the figure is alternated to –

Therefore, the complete figure is as follows –

Hence, the fourth option is correct.