The scum formed when soap is mixed with hard water could be

A. calcium trioxocarbonate (IV)
B. propane- 1, 2, 3 – triol
C. calcium hydrogentrioxocarbonate (IV)
D. magnesium tetraoxosulphate (IV)
E. calcium stearate

Correct Answer: Option A

A. calcium trioxocarbonate (IV)