What was the main obligation a knight owed to the lord from whom he held land?
Ploughing the lord's fields through the farming year
Paying a tenth of his produce to the lord
Military service, usually for a set number of days each year✓Correct answer
Unlimited service of every kind, owed for the whole of his life without any limit
Explanation
The whole point of granting land to a fighting man was to have soldiers on call, so his duty was to turn out armed, with his own horse and equipment, for a customary period whenever the lord summoned him. The idea of unlimited lifelong service fails because custom set a firm limit, and a lord who wanted men beyond it had to pay them or bargain for it.