Question: What is the Twitter username of the agent that has a subsidiary National Register of Historic Places?
Choices: galifianakisz
SirTimRice
LA_Reid
FAWales
EvansForIslwyn
NatlParkService
jon_vitti
davidakaye
edbegleyjr
TheNewSchool
SPARQL: SELECT DISTINCT ?pv WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "agent" . ?e <subsidiary> ?e_1 . ?e_1 <pred:name> "National Register of Historic Places" .  ?e <Twitter_username> ?pv .  }
Program:
function: Find
inputs: National Register of Historic Places
function: Relate
dependencies: 0
inputs: subsidiary
backward
function: FilterConcept
dependencies: 1
inputs: agent
function: QueryAttr
dependencies: 2
inputs: Twitter username
Answer: NatlParkService