Graph the given function.
f(x) = 7^x
Which key features apply to the graph?
A. The graph has an asymptote at y = 7 and is increasing as x approaches positive infinity.
B. The graph has an asymptote at y = 0 and is increasing as x approaches positive infinity.
C. The graph has an asymptote at y = 0 and is decreasing as x approaches positive infinity.
D. The graph has an asymptote at y = 7 and is decreasing as x approaches positive infinity.