Consider the series k=1∑∞k4k(x−1)2k. Which of the following correctly states its radius of convergence and the behavior of the series at x=3?
a) The radius of convergence is 1, and the series diverges at x=3.
b) The radius of convergence is 2, and the series diverges at x=3.
c) The radius of convergence is 2, and the series converges conditionally at x=3.
d) The radius of convergence is 4, and the series converges absolutely at x=3.