Not closely enough that it would have been considered low level at the time, if you look at the instruction set C isn't even close to one-to-one with the machine instructions. See https://en.m.wikipedia.org/wiki/PDP-11_architecture#Myth_of_... for why people might mistakenly think otherwise
With a modern compiler C isn't low-level. But under PDP-11 era C compilers, C really did map closely to processor instructions.