Sentence Correction

With less than thirty thousand dollars in advance ticket sales and fewer acceptances by guestspeakers than expected, the one-day symposium on art and religion was canceled for lack of interest.

A. less than thirty thousand dollars in advance ticket sales and fewer
B. fewer than thirty thousand dollars in advance ticket sales and less
C. fewer than thirty thousand dollars in advance ticket sales and fewer
D. lesser than thirty thousand dollars in advance ticket sales and fewer
E. less than thirty thousand dollars in advance ticket sales and as few

This is from Princeton Review. The explaination says that "when it comes to money, you use fewer if you are referring to the number of actual bills you have, but less if you are referring to the total amount and don't know the actual number of bills."

What is "actual bills" and "know the total amount but don't know the actual number of bills."

Can anyone provide me examples to make it clear?

I have 17 crisp one-dollar bills, 5 fewer than I had yesterday.

I have $17, $5 less than I had yesterday

A. less than thirty thousand dollars in advance ticket sales and fewer --> Both the comparison terms are correctly used...
Let's keep it...
B. fewer than thirty thousand dollars in advance ticket sales and less --> You can not use fewer here...As you mentioned, you should be using fewer in the context of the unit nouns such as money only when you are actually referring to the dollar bills and not to the dollar amount...Here, we are referring to dollar amount and not dollar bills...So, less is required...You can count acceptances..So, we need fewer at the end....
C. fewer than thirty thousand dollars in advance ticket sales and fewer--> Same as B..
D. lesser than thirty thousand dollars in advance ticket sales and fewer --> Lets keep it for the time being...
E. less than thirty thousand dollars in advance ticket sales and as few --> We need fewer, comparative form of few, because we are doing the comparison in the second part as indicated by than in the second half...When you have than explicitly mentioned in the sentence, then you have to use the comparative form of the adjective...

Whats the difference between less and lesser....I think both are comparative forms of little...
Little - Less/Lesser - Least...

As per Kevin's explanation, answer seems to be A.
Is that correct?