When a citizen is required to appear in a court, he is served with a a. subpoena
b. witness request
c. witness treaty
d. contract

A. subpoena.

Explanation:

A subpoena is a writ that orders a person to appear in a court of law. This document is a that summons a witness to be produced in a court, summoning the person to appear as a witness for any case. And if the person refused to appear in the court as ordered, then the court can put a case against that person for contempt of court order.

lincoln presided over the union victory in the american civil war, which dominated his presidency. a former whig, lincoln ran on a political platform opposed to the expansion of slavery in the territories. his election served as the immediate impetus for the outbreak of the american civil war.

lincoln won 212 electoral votes to mcclellan's 21 votes, and lincoln beat mcclellan. is the main reason lincoln won in 1864.