Question: What class of instruments was used by Stevie Nicks and Dido (the one that has the occupation of singer-songwriter)?
Choices: conga
Timbales
didgeridoo
tenor saxophone
oboe
maraca
xylophone
baritone saxophone
tambourine
guitar
SPARQL: SELECT DISTINCT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "class of instruments" . ?e_1 <instrument> ?e . ?e_1 <pred:name> "Stevie Nicks" .  ?e_2 <instrument> ?e . ?e_2 <pred:name> "Dido" . ?e_2 <occupation> ?e_3 . ?e_3 <pred:name> "singer-songwriter" .  }
Program:
function: Find
inputs: Stevie Nicks
function: Relate
dependencies: 0
inputs: instrument
forward
function: FilterConcept
dependencies: 1
inputs: class of instruments
function: Find
inputs: singer-songwriter
function: Relate
dependencies: 3
inputs: occupation
backward
function: Find
inputs: Dido
function: And
dependencies: 4
5
function: Relate
dependencies: 6
inputs: instrument
forward
function: FilterConcept
dependencies: 7
inputs: class of instruments
function: And
dependencies: 2
8
function: What
dependencies: 9
Answer: tambourine