Let h(x)=(x−1)1/3+2. Which statement correctly characterizes h′(x) as x→1?
a) h′(x)→0, so the tangent line is horizontal at x=1.
b) h′(x) approaches a finite non-zero constant equal to 31.
c) h′(x) grows without bound, indicating a vertical tangent at x=1.
d) h′(x)→−∞, showing a vertical tangent slanted downward at x=1.