Non-Verbal - Figure Matrix

DIRECTIONS : In each of the following questions, find out which of the answer figures (a), (b), (c) and (d) completes the figure matrix ?
Examples :

  A.   B.  
  C.   D.  
  Solutions : A.
In each row, the third figure comprises of a black circle and only those line segments which are not common to the first and the second figures.