Which layer of the CDM Architecture$$s four$-$layer hierarchy includes data integration and normalization?

$1.$

Layer A of the CDM Architecture four$-$layer hierarchy includes data integration and normalization.

$2.$

Layer B of the CDM Architecture four$-$layer hierarchy includes data integration and normalization.

$3.$

Layer C of the CDM Architecture four$-$layer hierarchy includes data integration and normalization.

$4.$

Layer D of the CDM Architecture four$-$layer hierarchy includes data integration and normalization.