The correct answer is (d).  Engels wrote these lines in his 1895 introduction to an edition of Marx’s The Class Struggles in France, 1848-1850.  In Engels’ view, the growing disparity of armed strength between the revolutionary proletariat and the bourgeois state meant that future revolutions would involve more than simply arming workers and calling them to the barricades.  In fact, he very presciently pointed out that the bourgeoisie will make every attempt to lure revolutionaries into armed confrontations where the odds are against them.. Engels’ focus in this essay is tactical rather than programmatic or moralistic.  He maintains that “revolution is the only true historical right,” and attempts to identify the forms of revolutionary activity best suited to the conditions of his time.

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