Answer:
A: 1,2-dimethylcyclopropane
Explanation:
The possible cyclic structure with formula C₅H₁₀ are shown in the image.
A is a cyclic compound. On monochlorination, A yields 3 products.
To have 3 products on monochlorination, there should be three different carbon atoms.
Considering structure 1, all carbons have same nature, thus only one product will be formed and thus not a structure of A.
Considering structure 2, there are two different carbon atoms, thus two different structure are formed and thus not a structure of A.
Considering structures 3 and 4 , there are four different carbon atoms, thus four products will be formed and either of them are not a structure of A.
Considering structure 5, there are three different carbon atoms, thus three different structure are formed and thus the A is structure 5.
