beside/besides

[vkhu]

Research in the work place reveals that people work for many reasons..............

A Beside money
B Besides money

The answer here is B but why can't I use A? I thought "beside" is an adverb? And even if it's a verb, isn't "many reasons" plural?

 

[JMurray]

Research in the work place reveals that people work for many reasons..............
A Beside money
B Besides money
The answer here is B but why can't I use A? I thought "beside" is an adverb? And even if it's a verb, isn't "many reasons" plural?

Here, "besides" is a preposition meaning "apart from", "other than".
"I have no way of making money besides the dishwashing job".

not a teacher​