ANSWER
[tex]P(A \cap B')=0.36[/tex]
EXPLANATION
If event A and event B are independent, then 
[tex]P(A \cap B)= P(A ) \times P(B)[/tex]
otherwise A and B are dependent events.
We were given that, 
[tex]P(A) = 0.4[/tex]
and
[tex]P(B) = 0.1[/tex]
and we were asked to evaluate 
[tex]P(A \cap B') [/tex]
Since A and B are independent,
[tex]P(A \cap B')  = P(A )  \times P(B') [/tex]
Recall that,
[tex]P(B')  = 1 - P( B)  [/tex]
This implies that,
[tex]P(A \cap B')  = P(A )  \times (1 - P(B) )[/tex]
We now substitute  the above values to obtain,
[tex]P(A \cap B')  = 0.4 \times (1 - 0.1 )[/tex]
[tex]P(A \cap B')  = 0.4 \times 0.9[/tex]
[tex]P(A \cap B')  = 0.36[/tex]
Therefore the correct answer is C.