Which two of the following types of metallic conduit REQUIRE threaded couplings? (Select two options.)

Which two of the following types of metallic conduit REQUIRE threaded couplings? (Select two options.)
A . Electrical metallic tubing (EMT)
B . Aluminum metal conduit (AMC)
C . Flexible metal conduit (FMC)
D . Intermediate metal conduit (IMC)
E . Rigid metal conduit (RMC)

Answer: D, E