Solution

Cyclomatic complexity formula:

$V(G) = E - N + 2P$

Where

$E$ = number of edges

$N$ = number of nodes

$P$ = number of connected components (here $P=1$)

From the graph:

Nodes = 10

Edges = 12

So,

$V(G) = 12 - 10 + 2(1)$

$V(G) = 4$