Question: Which was the person as doctoral student of Galileo Galilei?
Paraphrase: Which was the individual as doctoral understudy of Galileo Galilei?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P185 wd:Q307 . ?sbj wdt:P31 wd:Q5 } 
Answer: Ostilio Ricci