Answer:
A. If desks are a complementary good for desk lamps, the price of desks decreases.
D. If income increases and desk lamps are inferior goods.
E. If floor lamps are substitute goods for desk lamps, the price of floor lamps increases.
Explanation:
In order to increase the demand of the desk lamps, the options A, D and E seem suitable.
If desks are a complementary good for desk lamps, the price of desks decreases. People would buy more desks which would lead to an increase in lamp sales.
If income increases and desk lamps are inferior goods. that would mean that lamps are a cheaper commodity and is in income range.
If floor lamps are substitute goods for desk lamps, the price of floor lamps increases. This would lead to shift in demand from floor lamps to desk lamps.