Choose the correct combination of the following
A. Superphosphate of lime :
`Ca(H_(2)PO_(4))_(2).H_(2)O=2MgSO_(4).7H_(2)O`
B. Triple phosphate : `Ca(H_(2)PO_(4))_(2)`
C. Thomas slag : `P_(4)O_(10)+Ca_(3)(PO_(4))_(2)+Ca(NO_(3))_(2)`
D. Nitrophosphate : `Ca_(3)(PO_(4))_(2)+2Ca(NO_(3))_(2)`