Procrastinate perhaps? There are a few more that mean the same thing.
Its a verb that acts as a noun.

The harmonic frequency refers to the resonant frequency that is an integral multiple of the fundamental frequency, harmonics are usually simple sinusoidal oscillation at a single frequency. where as Resonance frequency are frequencies that are not necessarily sinosudal or integral multiple of fundamental frequency and it may have complex oscillations made up of multiple harmonics ~
It's like if you play a piano with a single key, it will show harmonic frequency, but if you use multiple keys at a time it may show Resonance.
The answer i believe is false <span />
A and D are grammatically correct! B and C are 100% incorrect.
In A, you can write "You are quite a..." as "You're quiet a...", but in D ,i don't see an error. So it's a 50-50 in my opinion.
I'm not a 100% sure on the right answer, but i can assure you that the answer is either A or D. Hope it helps!