Number of saturated hydrocarbons in C2H4,C2H2,C2H6,C3H8,C4H10,C4H6 C3H4,CH4 and C3H6 is/are

[Step 1]:The hydrocarbon in which all four free valencies of carbon are saturated with  hydrogen (or) carbon are called saturated hydro carbons.The formulae is  CnH2n+2 , where n = no.of carbon atoms[Step 2]:Therefore  n = 1,   CH4  n = 2,   C2H6,  n = 3,   C3H8,  n = 4,   C4H10, are saturated hydro carbons.