The pair of compounds representing isomers is
-
methane and ethane.
-
propane and butane.
-
butene-1 and butene-2.
-
propene and butene.
C
Correct answer
Explanation
Isomers are compounds with the same molecular formula but different structural arrangements. Butene-1 and butene-2 are structural isomers due to the position of the double bond.