The compound shown is treated with Na in liquid $\mathrm{NH}{}_3$ with ethanol. Which structure is the major product?

The compound is toluene. The methyl group is electron donating and remains on a double-bond carbon in the Birch product, 1-methylcyclohexa-1,4-diene. The alternative with the methyl on an sp3 carbon corresponds to an electron-withdrawing substituent, and the 1,3-diene and cyclohexane are not the Birch outcome.