[单选题]
For a diatomic quantum mechanical vibrator, the energy difference9ihc,:- fej* -hhau pp between adj:vznmhuf p+ u 799ada3acent qua u vm9n3aa7d p+uh9:fzntum states
A. increases as v increases.
B. decreases as v increases.
C. is constant for all values of v.
D. varies randomly as v increases.