Which of the Following Does Not Characterize the Per Gene

Multiple Choice

Which of the following does not characterize the per gene?

A) It controls duration of the circadian rhythm in fruit flies.
B) When mutated, it can alter behavioral phenotype.
C) It is highly conserved in diverse organisms.
D) Variants of this gene cause either short or long circadian periods.
E) In humans, a variant causes familial advanced phase sleep syndrome in which circadian rhythms are abolished.