The graphs are for a purely competitive market in the short run.
the graphs suggest that in the long run, assuming no changes in the given information, the market
a. supply curve will shift to the left.
b. supply curve shift to the right
c. demand curve will shift to the left.
d. demand curve will shift to the right

C- supply curve shift to the right

Explanation:

The supply curve will shift to the right in the long run, assuming all other factors are constant.

Firstly we need to understand that in  purely competitive market, there is strong competition and hence there are ample supply and demand to have fix a price as per market forces. However, in the long run, assuming that demand is constant, the number of suppliers increase as more suppliers enter the market. This increase in suppliers causes the supply curve to shift to the right which in turn helps in lowering of the price of a good. Hence, the new equilibrium price will be lower in long term due to increase in supply and no change in demand.