Hilltop Bank is an HDC of a note for $1,000 on which there is the forged signature of "Rob." If sued on the note by Hilltop, Rob's best defense would be

forgery.

Explanation:

In legal terms, forgery refers to falsifying documents or any other object of value and intend to negotiate it, collect it or benefit in any other way from it. But a forged document is not a valid document, therefore, the forged note that Hilltop Bank holds is no good. Forgery is a crime and it is a type of fraud.

answer may be d i think

d) social security number

let me know if i am correct or not, so i can edit the answer.