HOTSPOT You create a query that contains a procedure to display the top customers. The procedure breaks at runtime. 
Yeah, you need to run Open() after SetFilter because in AL the filter only affects records before opening the query. Replacing with SetRange or wrapping with BEGIN..END wouldn't fix it. Pretty sure that's all the question wants, but open to correction.
Microsoft loves to trick us with these order-of-operations questions. The only thing that actually fixes the runtime break here is adding Open() after you set the filter, not before. Everything else is a classic distractor. Pretty sure that's what they're after, but open to debate if someone sees differently.
Open() has to be after SetFilter, not before. Filters only take effect if set before opening the query, that's a key AL quirk. So only the option to add Open() right after SetFilter (not before) will actually fix things. Pretty sure this is the intent here, correct me if I missed something obvious.
