What is the difference between Nomura and RBC's estimate for the Japanese yen/euro currency pair by the end of Q1 2018?

The correct choice highlights the specific unit of measurement used in financial assessments of currency pairs. When discussing estimates or predictions for currency pairs like the Japanese yen/euro, the values are typically expressed in terms of the second currency of the pair relative to the first. In this context, a difference of 40 yen indicates a movement in the exchange rate, emphasizing the value of the Japanese yen against the euro.

When comparing predictions or estimates for currency pairs, it's essential that differences are articulated in the smallest unit of the primary currency in question—in this case, yen. This specificity allows for a clear understanding of how much the estimates vary, which is crucial for traders and analysts monitoring currency fluctuations. The other options would suggest inappropriate or irrelevant units for expressing differences in a currency exchange rate, which could lead to confusion or misinterpretation of the financial data.