Which of the following accurately lists transitions in western europe in the order in which they happened? a. the crusades-> the emergence of the feudal system -> the decline of the roman empire-> the emergence of towns and a middle class b. the emergence of towns and a middle class -> the crusades-> the decline of the roman empire-> the emergence of the feudal system c. the decline of the roman empire -> the emergence of the feudal system -> the crusades -> the emergence of towns and a middle class d. the emergence of the feudal system -> the decline of the roman empire -> the emergence of the feudal system -> the crusades