Which two scope values should an Architect recommend to UC?

Universal Containers (UC) wants to build a mobile application that twill be making calls to the Salesforce REST API. UC’s Salesforce implementation relies heavily on custom objects and custom Apex code. UC does not want its users to have to enter credentials every time they use the app .

Which two scope values should an Architect recommend to UC? Choose 2 answers.
A . Custom_permissions
B . Api
C . Refresh_token
D . Full

Answer: B,C