for each public key digital signature algorithm (RSA, DSA and ECDSA), a KAT shall be performed using at least one of the schemes approved for use in the FIPS mode. For example, if an RSA signature algorithm is self-tested using an X9.31-compliant scheme, it is not necessary to perform any additional known-answer tests for the implementations of the digital signature compliant with RSASSA-PSS or RSASSA-PKCS1-v1_5, even if these schemes are also supported by the module.