Que: Let, D = be a directed graph or digraph,then D’ = is a subgraph if ___________

a. A’ ⊂ A and R’ = R ∩ (A’ x A’)

b. A’ ⊂ A and R ⊂ R’ ∩ (A’ x A’)

c. R’ = R ∩ (A’ x A’)