Answer:
It is biased because it´s the american government inviting the people to buy war bonds.
Step-by-step explanation:
As the american government was trying to encourage people to buy war bonds to be able to finance the WWI efforts, the poster portrays a German soldier that is being rude with a young woman and you can see the background being burnt, this to reflect the barbarities and abuses that the german army was doing, and on this appeal to emotions and empathy the people would buy war bonds.