$B \rightarrow( p \vee q ) \wedge \sim p =( p \wedge \sim p ) \vee( q \wedge \sim p ) \ldots $ Distributive law
$= F \vee q (\wedge \sim p ) \ldots $ Complementary law
$= q \wedge \sim p \ldots $ Identify law
$=\sim p \wedge q \ldots $ Commutative law
Hence, $\sim p \wedge q$ is equivalent to $( p \vee q ) \wedge \sim p$