English to Spanish Art/Literary Other

This is the word used repeatedly in the following context in a textbook: Practice Problems
Directions: Label this exercise Unit 4 - Lesson 1, Set A, Set B, and Set C.
While I know that "conjunto" would probably be the correct technical term, I cannot imagine the student writing this over and over again throughout this 5-unit course. I have heard "set" in Spanish, but am wondering if we can use this or not because it is, of course, an "anglicismo", "barbarismo" or, my favorite, un "préstamo lingüístico". I would appreciate opinions.