If the double bond is broken heterolytically, formal charge pairs result, as shown in the other two structures. The preferred charge distribution will have the positive charge on the less electronegative atom (carbon) and the negative charge on the more electronegative atom (oxygen).
Single malt Scotch. Single malt Scotch is single malt whisky made in Scotland. To be a single malt scotch the whisky must have been distilled at a single distillery using a pot still distillation process and made from a mash of malted grain. In Scotland, the only grain allowed to be used in a single malt whisky is barley.
Since all whiskey is made from fermented grain mash, Scotch will obviously be no exception. To qualify as a scotch the spirit must be made from malted Barley, with many scotches using nothing more than barley, water and yeast. You are allowed to include whole grains of other cereals as well as caramel colouring.