Answer & Explanation:
For an organic compound to have four constitutional isomers, it must have four different possible ways of arranging its atoms. This typically occurs in compounds with at least four carbon atoms that have different structures. Some examples of organic compounds with four constitutional isomers could include butane (C4H10), pentane (C5H12), or hexane (C6H14). These compounds can have different structural arrangements due to variations in the positioning of their carbon-carbon bonds.