Answer is related to Explanation. Basis is a type of Explanation. 
Strength is related to Rest. Rest is related to Easy. Easy is related to Cake. Cake is related to Blow. 
Answer <--RelatedTo--> Explanation <--IsA-- Basis 
Strength <--RelatedTo--> Rest <--RelatedTo--> Easy <--RelatedTo--> Cake <--RelatedTo--> Blow 