Trends in Group 2 carbonates and compounds

Steps:

• Identify the statements: A on decomposition temperatures, B on hydroxide solubility, C on reducing agent strength.
• Recall thermal stability trend: Carbonate stability increases down Group 2 due to larger cation polarizing the CO3^2- ion less, so MgCO3 decomposes below 500°C while CaCO3 requires over 800°C.
• Check solubility trend: Hydroxide solubility increases down Group 2 as lattice energy decreases more than hydration energy, making Ca(OH)2 more soluble (Ksp ~10^{-6}) than Mg(OH)2 (Ksp ~10^{-11}).
• Check reducing agent trend: Standard electrode potentials show Ca (-2.87 V) more negative than Mg (-2.37 V), so Ca loses electrons more readily.

Not enough information due to incomplete D option.

Final answer: Not enough information.