Final answer:
The theme that both the painting and the poem reference is 'the exploitation of laborers by rulers', as both depict the struggle and unfair conditions of laborers in relation to absentee owners and rulers who benefit from their work.
Step-by-step explanation:
The theme best expressed by both the painting and the referenced lines from the poem appears to center on the exploitation of laborers by rulers. This theme is underscored in the detailed analysis of the hardships that laborers faced during the rise of industrialism. The sources cited discuss the low wages, dangerous conditions, and the absentee owners who profited from the laborers' toil. For instance, in both the painting 'The Gleaners' and Marx's book 'Das Kapital', we witness a stark portrayal of the struggle faced by the working class and the criticism of the socio-economic systems that allow for such exploitation to occur. Therefore, the appropriate theme expressed would be option 1: The exploitation of laborers by rulers.