The correct answer is: c) Occasionally tense.
Relations between feudatory states and the Kangleipak kingdom were occasionally tense. The feudatory states were often jealous of the Kangleipak kingdom’s power and wealth, and there were occasional conflicts between them. However, there were also periods of cooperation, when the feudatory states would work together to defend themselves against outside threats.
Option a) is incorrect because relations between feudatory states and the Kangleipak kingdom were not always peaceful. There were occasional conflicts between them.
Option b) is incorrect because relations between feudatory states and the Kangleipak kingdom were not often cooperative. There were more periods of tension than cooperation.
Option d) is incorrect because relations between feudatory states and the Kangleipak kingdom were not mostly hostile. There were periods of cooperation, and the feudatory states were not always hostile to the Kangleipak kingdom.