70% have VCD Players. 30% do not have VCD Players.
75% have microwave ovens. 25% do not have microwave ovens.
80% have ACs. 20% do not have ACs.
85% have washing machines. 15% do not have washing machines.
30 + 25 + 15 + 20 = 90% of employees do not have atleast 1 gadget.
Minimum percentage of employees who has all the four gadgets
= 100 – 90 = 10%
Hence, option(C)10% is the Answer..