Question: Of rivers that are tributaries of the Mississippi River, which has the greatest discharge volume?
Choices: Ohio River
Danube
Columbia River
Amazon
Hudson River
Missouri River
River Thames
Mississippi River
Rhine
Jeff Richmond
SPARQL: SELECT ?e WHERE { ?e <pred:instance_of> ?c . ?c <pred:name> "river" . ?e_1 <tributary> ?e . ?e_1 <pred:name> "Mississippi River" .  ?e <discharge> ?pv . ?pv <pred:value> ?v .  } ORDER BY DESC(?v) LIMIT 1
Program:
function: Find
inputs: Mississippi River
function: Relate
dependencies: 0
inputs: tributary
forward
function: FilterConcept
dependencies: 1
inputs: river
function: SelectAmong
dependencies: 2
inputs: discharge
largest
Answer: Ohio River