Which of the following statements about the child tax credit is true? a. The credit would not be available for an 18-year-old child who is a full-time student. b. Taxpayers who have two qualifying children are allowed to claim only one credit. c. A married couple with AGI of $150,000 would be entitled to claim a credit for their only child who is 2 years old. d. The credit is not refundable e. More than one of the above is true