Which of the following beers is most likely to be amber in color?

The choice of Octoberfest as the beer most likely to be amber in color is based on the style characteristics typically associated with this specific type of beer. Octoberfest, originating from Germany, is known for its rich, malty flavor and amber to deep amber coloration. This hue comes from the use of Munich malt which provides both sweetness and a darker color, contributing to the overall visual and taste profile of the beer.

In contrast, German Pilsner and Bohemian Pilsner are styles that emphasize a pale straw to golden color resulting from the use of pale malt and a focus on hop character, rather than malt sweetness and richness. Munich Dunkel, while darker than lighter lagers, typically presents a very dark brown color rather than the clear amber of Octoberfest. Thus, the distinctive amber color of Octoberfest makes it the clear choice among the options provided.