During the golden age, the chinese leadership practiced a policy of isolationism. which is the best reason this was policy?

the country was self sufficient in all needs.
the leaders believed they were the center of the world and all other countries were inferior.
the leaders believed all other countries should model the practices of china.
chinese leadership did not know of other countries of the world to interact with.

when a country suffers, for example, a drought period, the market product is affected for a low offer, in this case, potatoes; the government has to tax to the households, which have to give more money for the potatoes which they consume, that situation make them consume substitute goods even through loans, it could increase the financial market movement and the inflationary phenomena, the business has to increase salaries in order to the employees could buy a more expensive food (potatoes) and in order to inflation tha business had to buy expensive supplies in the factor market, while the rest of the world have to gain more money to consume the same amount of potatoes.

it proved indian land claims were unjustified.