Which meaning of the vocabulary word patent is used in the following excerpt from "The Gift of the Magi"

“You’ve cut off your hair?” asked Jim, laboriously, as if he had not arrived at that patent fact yet even after the hardest mental labor.
A) Obvious
B) Bold
C) Original

A) Obvious

In this context, the word "patent" is referring to something that is clearly or obviously true. Jim is struggling to come to terms with the fact that Della has cut off her hair, even though it is plainly evident.