Question: What organization's member is the person who is the U. S. Congress chairperson?
Choices: McDonald's
Schutzstaffel
John Brown & Company
Academy of Television Arts & Sciences
E. W. Scripps Company
Pfizer
Congressional Progressive Caucus
AT&T
Image Comics
BBC
SPARQL: SELECT DISTINCT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "organization" . ?e_1 <member_of> ?e . ?e_1 <pred:instance_of> ?c_1 . ?c_1 <pred:name> "human" . ?e_2 <chairperson> ?e_1 . ?e_2 <pred:name> "United States Congress" .   }
Program:
function: Find
inputs: United States Congress
function: Relate
dependencies: 0
inputs: chairperson
forward
function: FilterConcept
dependencies: 1
inputs: human
function: Relate
dependencies: 2
inputs: member of
forward
function: FilterConcept
dependencies: 3
inputs: organization
function: What
dependencies: 4
Answer: Congressional Progressive Caucus