A certain hydrocarbon containing eight carbons was found to have two degrees of unsaturation
but, no absorption bands in the IR spectrum at 1640cm-1
. The best structure for this compound is: A. 1,2,3,3a,4,6a-hexahydropentalene B. Butylcyclobutane d. 1-cyclopropylethylcyclopropane c.pentylidenecyclopropane