The strike price must be $1.55 = €1.00 
Step-by-step explanation:
Dollar is the name of the currency used in America. Euro is the name of the currency used in European countries. 
Strike price is a fixed price at which the product is purchased or sold. 
Given: 
The exchange rate of currency = $1.55 = €1.00 
Three-month forward rate = $1.60 = €1.00 
The strike price must be $1.55 = €1.00