Which of the Following Is True About Signing Statements

Which of the following is true about signing statements?

A) They are written declarations that a president may make when signing a bill into law regarding the law's enforcement.
B) They can only be used to make rhetorical statements.
C) They cannot be used to praise or denounce political parties.
D) They were used frequently in the nineteenth century, but are rarely used today.
E) They were used by President Reagan to make more sweeping claims on behalf of presidential power than any other president.