# S1: Magnetic flux is vector quantity.  S2: Value of magnetic flux can be positive, negative or zero.

$\begin {array} {1 1} (a)\;\text{S1 and S2 are true; S2 is a correct explanation of S2.}\\ (b)\;\text{S1 and S2 are true; S2 is not a correct explanation of S1.} \\ (c)\;\text{S1 is true; S2 is false} \\ (d)\;\text{S1 is false; S2 is true.} \end {array}$

$\phi = B . A = BA\: cos\theta$
Since, flux is a dot product of vectors $B$ and $A$, hence flux is a scalar quantity.
If $\theta$ = acute angle, $\cos\theta$ is positive
and if $\theta$ obtuse angle,
$\cos \theta$ is negative
and if $\theta$= right angle, $\cos\theta = 0$
Ans : (d)