Answer
Consumer surplus and producer surplus both increase. The government loses tax revenue (due to the subsidy). Total surplus decreases, and there is a deadweight loss.
Work Step by Step
In the graph, the original equilibrium quantity and equilibrium price (respectively) are $Q_{0}$ and $P_{0}$. The original consumer surplus is the sum of areas $A+B$, and the original producer surplus is the sum of areas $C+D$. There is no tax revenue, and total surplus is the sum of areas $A+B+C+D$.
With the subsidy, the equilibrium quantity and equilibrium price (respectively) are $Q_{1}$ and $P_{C}$.
The new consumer surplus is the sum of areas $A+B+C+F+G$, and the new producer surplus is the sum of areas $B+C+D+E$. There is now a loss of tax revenue of the sum of the areas $B+C+E+F+G+H$, and total surplus is now the sum of areas $A+B+C+D-H$.
Since total surplus was $A+B+C+D$, and now total surplus is $A+B+C+D-H$, there is a deadweight loss of $H$.
