1 is clearly not enough on its own

2)

Sq both sides

x^3 - 9x + 4 > 4

x(x^2 - 9) > 0

x(x-3)(x+3) > 0

the above holds true for all x>3, and but also for say x = -1, so not sufficient

Combining 1 and 2, we know that x > 0, and for x(x-3)(x+3) > 0 to hold true with that precondition, x must be greater than 3

hence (C)

OA please?

When U take option B

we get
1. x>0
2.x>-3
3.x>3

Now as Option A gives x>0 hence x>-3 is eliminated.

But combing still does not tell us that x>3 because Option a and b give us just that x>0

So how come option C is the answer