Final answer:
b). The least basic oxide among the given options is Mgo (Magnesium oxide).
Step-by-step explanation:
The least basic oxide among is Mgo (Magnesium oxide).
Basic oxides are compounds that react with water to form a base or an alkali. They are usually oxides of metals and produce hydroxide ions (OH-) when dissolved in water.
In this case, BeO (Beryllium oxide), CaO (Calcium oxide), and SrO (Strontium oxide) are all highly basic oxides. However, Mgo is less basic compared to the other options because magnesium is less reactive than beryllium, calcium, and strontium.
Learn more about basic oxides