We've moved onto a new page so it might be helpful to repeat the answers and questions so far. The theme, as discovered by Olinguito, is men who have walked on the Moon. (Note that question A has a connection to the astronaut himself, but the others don't.)
A. 12790 - What is the numerical designation of the minor planet named after Gene Cernan?
B. An accountant
C. The battle of Waterloo
D. Cliff Richard
E. Hollinger International
G. The Northern Ireland peace process
H. An organochlorine insecticide in use until the 1990s
I. A stingray
J. The Third Reich
K. The trumpet - What instrument is the jazz musician Louis Armstrong noted for playing?
L. A type of auditory illusion