Compound j is optically active and has the molecular formula c6h10 and has a four carbon ring. on catalytic hydrogenation, j is converted to k (c6h12) and k is optically inactive. propose structures for j and k. (draw a three-dimensional formula for each using dashes and wedges around chiral centers.) j (draw one of the enantiomers):

The two possible enantiomers for the starting material and the products are shown below,

Where;
               J  =  (S)-1,4-dimethylcyclobut-1-ene
Or,
               J  =  (R)-1,4-dimethylcyclobut-1-ene
And,
               K  =  1,2-dimethylcyclobutane

Both enantiomers have same molecular formula (C₆H₁₀) but different stereochemistry about chiral carbon.

Upon catalytic hydrogenation two hydrogen atoms are added across double bond resulting in the formation of cyclobutane. 

Decomposition is the cycle at which bacteria breaks down any organic material into the soil

Sorry i think the answer is b