In a triangle, the length of the two sides are 5 cm and 7 cm. What can be the length of the third side?
Correct: B
According to the triangle inequality theorem, the sum of the lengths of any two sides of a triangle must be greater than the length of the remaining side. So, the third side must be less than 5 + 7 = 12 cm and greater than 7 - 5 = 2 cm. Therefore, the length of the third side must be greater than 2 cm and less than 12 cm.