You can basically think of Dicumarol as warfarin.
MOA: Depletes vitamin K stores
Since Vitamin K is involved in gamma carboxylation of factors 2, 7, 9, & 10, you can use the Prothrombin Time to measure the response. Prothrombin time measures the extrinsic pathway of coagulation, which is mainly mediated via Factor 7.
If you don't know what Dicumarol does like any normal human. The focus on what aspirin doesn't do, namely it's doesn't affect PT time and most pills don't increase clotting (especially with aspirin). This is how I logic to the right answer.
Can anyone tell the effect of aspirin on a blood lab value (i.e PT,PTT,Fibrin product)?