Question: What was the sovereign state for the diplomatic relations of the German Democratic Republic?
Paraphrase: What was the sovereign state of the German Democratic Republic's diplomatic relations?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P530 wd:Q16957 . ?sbj wdt:P31 wd:Q3624078 } 
Answer: Serbia, North Korea, Israel, Pakistan