How can the informal sector be improved so as to contribute meaningfully to the economy?

Improving the conditions and opportunities for the informal trading sector can lead to overcoming socio-economic hardships associated with unemployment and hunger. 
But, the informal economy can also contribute to growth of the economy.
One way is traders to pay levies and fees for various administration processes, which are ultimately related to the use of public space and amenities. That way the country economy will also have benefit from the informal trading.

The answer is c) people evacuated but almost all returned