The length of two sides of a triangle are 7 cm and 9 cm. The length of the third side may lie between

Difference of 2 sides of triangle is always smaller than the 3^rd side of triangle

Difference = 9cm – 7cm = 2cm

∴ 3^rd side must be greater than 2cm

And

Sum of 2 sides of triangle is always greater than 3^rd side of triangle

Sum = 9cm + 7cm = 16cm

∴ 3^rd side must be smaller than 16cm

Hence;

Appropriate option comes out to be (C). 3 cm and 16 cm