Given the following small project for an AOA network:

$\backslash$table$[[$Activity$,$Immediate Predecessor$($s$),$Time Duration $($days$)],[$A$,$D$,7],[$B$,$D$,6],[$C$,$A$,$ B$,5],[$D$,$None,$4],[$E$,$D$,13]]$

How many nodes in this AOA network should be there totally?

Keep your own AOA graph.

Select one:

a$.5$ nodes

b$.7$ nodes

c$.4$ nodes

d$.6$ nodes

e$.3$ nodes