Must is related to Responsibility. Responsibility is related to Blame. Blame is related to Finger. Finger is related to Extension. 
Option is a type of Contract. Partnership is a type of Contract. 
Must <--RelatedTo--> Responsibility <--RelatedTo--> Blame <--RelatedTo--> Finger <--RelatedTo--> Extension 
Option --IsA--> Contract <--IsA-- Partnership 