In what design is the cause-and-effect argument strongest?

Which of the following is the largest source of most Texas cities' revenues?

A. sales tax revenue B. federal transfer payments C. state funding D. property taxes

Under which of the following circumstances would the president convene Congress?

a. The president wants to appoint a justice for the Supreme Court. b. The president declares a national day of mourning upon the death of a former president. c. The Congress has gone on strike and refuses to convene itself. d. The president declares war on a foreign country that has attacked the United States militarily.