Study the given flow chart and fill in the blanks by selecting an appropriate option.
| (i) | (ii) | (iii) | (iv) | (v) | (vi) | (vii) | |
| A | Oxide | Neutral | Acetic acid | Sulphuric acid | NaNO3 | CaCO3 | H2 |
| B | Base | Salt | Tartaric acid | Formic acid | Na2CO3 | Ca(OH)2 | CH4 |
| C | Base | Salt | Phosphoric acid | Formic acid | NaHCO3 | Cu(OH)Cl | H2 |
| D | Oxide | Neutral | Formic acid | Acetic acid | HNO3 | CaO | O2 |