Which of the Following Best Matches the Description

Which of the following best matches the description?
-A serious effect that occurs after prolonged exposure to small doses of a toxin.

A) Superfund
B) synergism
C) CERCLA
D) acute toxicity
E) LD₅₀
F) RCRA
G) National Priority List
H) threshold levels
I) Superfund.
J) chronic toxicity
K) corrosiveness
L) ignitability
M) reactivity
N) waste minimization
O) toxicity
P) hazardous wastes