How would a developer write the Exclusion Script?

NTO wants to exclude sending an email at send time to those with a record on the ‘Exclude’ Data Extension. The primary key on this data extension is Subscriber Key.

How would a developer write the Exclusion Script?
A . Lookup (‘Exclude’,’EmailAddress’,’SubscriberKey’,SubscriberKey)
B. Lookup (‘Exclude’,’SubscriberKey’, ‘EmailAddress’, emailddr_)
C. Rowcount (LookupRows(‘Exclude’,SubsciberKey,_SubscriberKey) >0
D. Rowcount (LookupRows(‘Exclude’,’SubscriberKey,_SubscriberKey) >1

Answer: C