Answer:
B. 12cm,7cm,5cm
Step-by-step explanation:
use triangular inequality therom
A+B>C 12+7>5 true
B+C>A 7+5>12 false
A+C>B 12+5>7 true
One of the sides is not complete so it can not be a triangle.
Answer is option-B
Triangle Inequality Theorem :
In Euclidean geometry, theorem that the sum of any two sides of a triangle is greater than the third side; in symbols,
a + b > c.
a + c > b
b + c > a
(Here)
For option-B
let's take a = 12cm, b = 7cm and c = 5cm.
b + c = a.
It violates triangle Inequality property.
Learn more about Triangle Inequality theorem here: https://brainly.com/question/1163433?referrer=searchResults
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