c is foreign key referring to A, means if ( 4,3) is deleted , 4 will not be in C(foreign key) so tuple (2,4), (3,4), (6,4) will be deleted then , now , Primary key value 2, 3 ,6 deleted so they also will not be in C as foreign key ... so tuple (5,2) , (7,2) are removed now in similar way 5 , 7 are deleted so (9,5) also deleted so total additional 6 tuples will be deleted