Discussion

Explanation:

If a², b² and c² are three sides of a triangle then sum of any two sides of the triangle must be greater than third i.e. a² + b² > c². 

Now for a triangle with sides a, b and c, it is 

Acute triangle if, a² + b² > c²
Right triangle if, a² + b² = c²
Obtuse triangle if, a² + b² < c²

∴ Triangle with sides a, b and c will be an acute triangle.

Hence, option (a).

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