From pie chart =>
X + Y + 12 + 21 + 17 = 100
X + Y = 50
Y = 50  -  X ------(1)
Let total number of items manufactured by the company = P
Number of unsold fans / Number of sold television = 6/7
[(100  -  X  -  15)% of 12% of P]/[(X  -  Y)% of X% of P] = 6/7
12(85  -  X)/[X(X  -  Y)] = 6/7
14(85  -  X) = X[X  -  (50 - X)]
1190  -  14X = 2X2  -  50X
X2  -  18X  -  595 = 0
X2  -  35X + 17X  -  595 = 0
(X  -  35)(X + 17) = 0
X = 35, -17
X = 35 (Positive value)
Y = 50  -  35 = 15
Number of unsold coolers and refrigerators together = Number of fans sold  -  18
[(100  -  6Y)% of 21% of P] + [(100  -  75)% of Y% of P] = [(X + 15)% of 12% of P]  -  18
21P(100  -  6*15) + 25P * 15 = 12P(35 + 15)  -  180000
7P*10 + 25P * 5 = 4P*50  -  60000
(200  -  70  -  125)P = 60000
5P = 60000
P = 12000
Total number of items manufactured by the company = 12000
For television =>
Manufactured = 35% of 12000 = 4200
Sold = (35  -  15)% of 4200 = 840
Unsold = 4200  -  840 = 3360
Similarly, we can calculate for other items.
| Item | Manufactured | Sold | Unsold | 
| Television | 4200 | 840 | 3360 | 
| Refrigerator | 1800 | 1350 | 450 | 
| Fan | 1440 | 720 | 720 | 
| Cooler | 2520 | 2268 | 252 | 
| Washing machine | 2040 | 1428 | 612 | 
I: Ratio of the number of unsold fans and washing machine = 720:612 = 20:17 (True)
II: Difference between the number of sold and unsold television = 3360  -  840 = 2520 > 2500 (False)
III: Number of refrigerators manufactured = 1800
Number of fans manufactured = 1440
1800  -  1440 = 360 (True) 
Hence, option 'c' is correct.