Question: What agent's headquarters is located in the town that is the birthplace of Glenda Jackson?
Choices: Vodafone
Pfizer
First Continental Congress
Sega
KLM
Silver Pictures
GT Interactive Software
McDonald's
Cammell Laird
Tranmere Rovers F.C.
SPARQL: SELECT DISTINCT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "agent" . ?e <headquarters_location> ?e_1 . ?e_1 <pred:instance_of> ?c_1 . ?c_1 <pred:name> "town" . ?e_2 <place_of_birth> ?e_1 . ?e_2 <pred:name> "Glenda Jackson" .   }
Program:
function: Find
inputs: Glenda Jackson
function: Relate
dependencies: 0
inputs: place of birth
forward
function: FilterConcept
dependencies: 1
inputs: town
function: Relate
dependencies: 2
inputs: headquarters location
backward
function: FilterConcept
dependencies: 3
inputs: agent
function: What
dependencies: 4
Answer: Cammell Laird