In any triangle the sum of any 2 sides should be smaller to the third:
a + b > c
A (4,10,6): 4+6 = 10. Then it's not a triangle
B (4,7,11): 4+7 = 11. Then it's not a triangle
C (4,7,7) :( 4+7 > 7), (7+7 > 4): It's a triangle
D (4,10,3): (4+10>3) ; (10+3>4) BUT (4+3 IS SMALLER THAN 10). So this is not a reiangle
