Which exclusion query should be used?

After the ground water is the local community was contaminated by a landfill, the health department requested a map showing the cancer rate for each postal code. An ArcGlS user Is provided a file geodatabase feature class (FeatureClassA) that has been joined to a cancer rate table (TableB). The cancer rate table does not have data for each postal code In the study and also contains data outside the study area creating null values. To eliminate the null values from being symbolized.

Which exclusion query should be used?
A . (FeatureClassA OBJECTED is Not Null) and (Table
B . cancerrate Is Not Null)
C . ("FeatureClassA OBJECTED" is Not Null) and (Table
D . cancerrate is Not Null)
E . ("FeatureClassA OBJECTED". "TableB cancerrate" is Not Null)
F . ("FeatureClassA OBJECTED" and "TableB cancerrate" is Not Null)

Answer: A