Question: Which form of music is practiced in hardcore punk, reggae and ska and features guitar strumming techniques including the upstroke and bang? 
Sentence (from "Ska stroke"): In reggae, the guitar usually plays a short, percussive, "scratchy chop sound [chord]," on beats 2 and 4 (1 2 3 4), often supported by staccato piano (late 1960s to the early 1980s) or synthesizer.
Relevant evidence: No