Biology: Which species of Elephant has the largest ears ?

Questions

Which single word connects a Beethoven composition, a Glenn Miller melody and some Terry's chocolates?

What is the venue for the coursing Waterloo Cup?

What is the name of the Buckinghamshire estate where the German Enigma codes were cracked during World War 2?

What single word connects the Spanish Armada, and the two TV programmes, Danger Man and The Worker?

Which classic British car company of the 1940s and 1950s now produces armoured vehicles for the British military?