Question: When did the thrash metal that origins from Canada begin?
Choices: 1867-01-01
1738-08-01
1985-01-01
1857-04-22
1793-01-01
1786
1811-02-09
2004-11-01
1931-03-31
1975-07-06
SPARQL: SELECT DISTINCT ?pv WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "thrash metal" . ?e <country_of_origin> ?e_1 . ?e_1 <pred:name> "Canada" .  ?e <inception> ?pv .  }
Program:
function: Find
inputs: Canada
function: Relate
dependencies: 0
inputs: country of origin
backward
function: FilterConcept
dependencies: 1
inputs: thrash metal
function: QueryAttr
dependencies: 2
inputs: inception
Answer: 1985-01-01