Explanation:

Correct answer is (e). If we read both the sentences carefully we can observe that the sentence II refers to an event of past which is related to time (year 2013) whereas sentence I talks about an event that happened recently. Clearly, none of the given connectors seems to fit in.
However, we can connect these two statements using ‘when’ as connector.
The fall in value of Rupee has raised fears of a repeat of the currency crisis of 2013 when the rupee suffered a drastic loss of about 20% in just a few months.Clearly, option E is the correct answer.