If MAC is more restrictive than DAC, why does Windows include the use of DAC when granting access?

a$.$ because Windows' version of DAC includes SIDs and integrity levels on every object

b$.$ because it first checks any requests against MIC and, if they pass, it then checks DAC

c$.$ because it first checks any requests against MAC and, if they pass, it then checks DAC

d$.$ because Windows assigns users, processes, and devices a privilege label in its DAC implementation

e$.$ because Windows uses a highly secure version of DAC that provides the needed level of protection