What are the minimum entries you need in the dfc.properties file to turn on tracing?

A.
dfc.tracing.enabled=true dfc.tracing.file=<file_path>

B.
dfc.tracing.enabled=true

C.
dfc.tracing.enabled=true dfc.tracing.file=<file_path> dfc.tracing.level=<level>

D.
dfc.tracing=true