Choose the correct word to fill in the blank in the given sentence:-

In _____, I think I should have been more patient with my learning process.

retrospect

The correct answer is Option (3) → retrospect

The sentence "In _____, I think I should have been more patient with my learning process" implies looking back at a past event or period and reflecting on it with newfound understanding or regret. 

Retrospect: A survey or review of a past course of events or period of time. The phrase "in retrospect" specifically means "when looking back on a past event or situation, especially with the advantage of hindsight." This perfectly fits the context of reflecting on a past learning process and realizing something.

• Memory: Refers to the faculty by which the mind stores and remembers information, or a particular recollection of an event. While it involves the past, "in memory" doesn't quite fit the idiomatic expression of reflection.

• Recollection: The act of recalling a past event or fact, or the faculty of doing so. Similar to memory, it's about remembering.

• Reminiscence: The enjoyable recollection of past events. While it involves looking back, it usually carries a connotation of pleasant or nostalgic memories, and the sentence implies a learning or even regretful reflection, not necessarily just pleasant recall.