Step 1: Understanding the Question:
The problem requires us to match classification categories of triangles (based on sides and angles) to their corresponding dimensional or angle properties.
Step 2: Detailed Explanation:
Let us analyze each type of triangle listed in List-I:
• Equilateral Triangle (A): A triangle where all three sides are equal. Description III states "each side being 5 cm", which means all sides are equal. Thus, A matches III.
• Isosceles Triangle (B): A triangle where at least two sides are equal. Description IV defines a triangle with sides "4 cm, 6 cm and 6 cm", showing two equal sides. Thus, B matches IV.
• Acute Angle Triangle (C): A triangle where all three interior angles are strictly less than $90^\circ$. Description I gives angles of $70^\circ$, $60^\circ$, and $50^\circ$, all of which are acute. Thus, C matches I.
• Obtuse Angle Triangle (D): A triangle with exactly one angle greater than $90^\circ$. Description II has an angle of $130^\circ$, which is obtuse. Thus, D matches II.
Step 3: Final Answer:
The matching sequence is A-III, B-IV, C-I, D-II, which corresponds to option (D).