Which of the following statements is true?

a. the ratio test says that the series converges absolutely.
b. the ratio test says that the series diverges.
c. the ratio test says that the series converges conditionally.
d. the ratio test is inconclusive, but the series converges absolutely by another test or tests.
e. the ratio test is inconclusive, but the series diverges by another test or tests.
f. the ratio test is inconclusive, but the series converges conditionally by another test or tests

choose one or more options and explain why those options are true.