Option A

Correct
If DST is delayed by 3 weeks, then there would be more day light. Hence, people who stay away from stores after dark will still come for another three weeks. Let's assume the store closing time is 7PM. If DST is not adjusted, then 7PM will be still bright. If DST is adjusted, then 7PM will be dark. Hence if it is delayed by 3 weeks, then the store can attract those customers who are wary of shopping in the dark

These people would remain outdoors irrespective of daytime or night-time. Irrelevant

What they spend on overall during the fall is irrelevant. What matters is whether they purchase during daytime

Same as C)

No relationship
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