Which selection is correct for making a clean orange in a split-primary palette?

Correct answer: Warm red and warm yellow

In a split-primary system, a clean secondary colour is obtained by choosing two primaries that lean toward it. Warm red generally carries a yellow bias, while warm yellow carries a red bias; together they reinforce orange and create a brighter mixture. Therefore option A is correct. Options B and D include blue influences, and option C is directed toward green rather than orange.