22) D

Options A and C are wrong because they are alkenes.
Let molecular formula of alkane be CxHy

Ratio of volumes of alkane and CO2 = 35 : 105 = 1 : 3

This means that number of carbons (x) = 3

Only options C and D have hydrocarbons where number of carbons are 3. We have already established that option C is wrong because it is an alkene so option D is correct.