Which phrase indicates that men were unprepared for hard labor?

The phrase "Perfectly unfitted by previous habits" indicates that men were unprepared for hard labor because it directly suggests that their past experiences and influences have not equipped them for the demands of such work. This description highlights a contrast between their previous lifestyles and the labor they now face, implying that their prior habits have rendered them unable to grapple with the physical and mental challenges that hard labor entails.

In this context, the other phrases do not convey the same sense of unpreparedness. "Wield the spade and guide the plough" denotes an action associated with agricultural labor, implying readiness rather than unpreparedness. "Contending with stern realities" suggests a confrontation with difficult situations but does not specifically address preparedness or lack thereof. "Made to believe in rain of gold" implies a false sense of security or unrealistic expectations but does not directly indicate a lack of preparation for hard work. Therefore, the chosen phrase effectively encapsulates the idea of unpreparedness for hard labor.