Correct Answer: A. Li
Detail about MCQs
Among the elements listed, the element that forms only a normal oxide (also known as a basic oxide) is: Li (Lithium)
Lithium forms lithium oxide (Li2O), which is a normal oxide. Normal oxides are basic in nature and react with water to form hydroxides. In contrast, elements like sodium (Na), potassium (K), and rubidium (Rb) can form both normal oxides and peroxides, depending on the conditions.