Which statement best characterizes a removable discontinuity of a real-valued function at x=c?
a) Both one-sided limits exist and are equal, and the function value at x=c equals that common limit.
b) The limit as x→c is infinite, indicating a vertical asymptote at x=c.},{
c) The two-sided limit as x→c exists and is finite, but f(c) is either undefined or not equal to that limit.
d) The left-hand and right-hand limits differ at x=c, even though f(c) is defined.