Eulerian and Hamiltonian Graphs · Easy problem

Four landmasses $A,B,C,D$ are joined by bridges: two separate bridges between $A$ and $B$, one bridge $A$–$C$, one bridge $B$–$D$, and two separate bridges between $C$ and $D$ ($6$ bridges total, modeled as a multigraph where parallel bridges are separate edges). How many of the four landmasses have an odd number of bridges?