I think the right answer is C.(William Penn)
D. Remained poor.
They experienced a period of economic stagnation following the independence. Making a lot of people remained poor despite being free from the European colonization. They need some time before they eventually make adjustments to implement a proper political system in place and develop their economy.
Na/K concentration in and out of the cell at the homeostatic level. It does this by pumping sodium and potassium ions in and out when it's needed of it in order to maintain the concentration of both ions stable across time.