What's the next number in the series 6 17 - 5 28 - 16? A,17 B,-5 C,-71 D,39

What's the next number in the series 6 17 - 5 28 - 16? A,17 B,-5 C,-71 D,39

The third is the fourth
So the next one should be: - 5 + 28 - (- 16) = 39
So choose D