Solution; 

Let the man's age be 'x' his wife's age be 'y' and his son's age be 'z'.

It is given that the man is 3 years older than his wife and four times as old as his son so,

$x = y + 3 -------> 1$

$x = 4z -----------> 2 $

It is also given that the man's son become 15 years old after 3 years so,

$z + 3 = 15$

So, $z = 15 - 3 = 12$

Substituting the value of z in equation 2 we get 

$x = 4 × 12$

$x = 48$

Substituting the value of x in equation 1 we get 

$48 = y + 3$

$y = 48 - 3$

$y = 45$

So, the present age of the man's wife is 45 years.

The correct option is 4). 45 years