Final answer:
Functional hypothesis is not a primary assessment typically used to determine the function of SIB.
Step-by-step explanation:
The primary assessments that Rachel, an RBT, and Jenna, her supervising BCBA, might use to determine the function of an adult client's Self-Injurious Behavior (SIB) would typically include a) Functional Behavioral Analysis, b) observation, c) ABC data recording, and d) functional hypothesis. Of these options, the exception would be d) functional hypothesis. This assessment technique is not typically used as a primary assessment method to determine the function of SIB.