<Dd> <Ol> <Li> Investigative Mission--The investigative mission of the USSS is to safeguard the payment and financial systems of the United States from a wide range of financial and electronic - based crimes . </Li> <Li> Protective Mission--The protective mission of the USSS is to ensure the safety of the President of the United States, the Vice President of the United States, their immediate families, and foreign heads of state . </Li> </Ol> </Dd> <Ol> <Li> Investigative Mission--The investigative mission of the USSS is to safeguard the payment and financial systems of the United States from a wide range of financial and electronic - based crimes . </Li> <Li> Protective Mission--The protective mission of the USSS is to ensure the safety of the President of the United States, the Vice President of the United States, their immediate families, and foreign heads of state . </Li> </Ol> <Li> Investigative Mission--The investigative mission of the USSS is to safeguard the payment and financial systems of the United States from a wide range of financial and electronic - based crimes . </Li> <Li> Protective Mission--The protective mission of the USSS is to ensure the safety of the President of the United States, the Vice President of the United States, their immediate families, and foreign heads of state . </Li>

Which part of dhs oversees the integrity of the nation's financial infrastructure
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