Step 1: Understanding the Concept:
The question requires matching different styles of Hindustani vocal music (Gayan Shaily) with their characteristic elements or forms of elaboration.
Step 2: Detailed Explanation:
- (A) Khayal: A prominent feature of Khayal singing is the use of 'Tanas', which are fast-paced melodic passages sung on vowels. So, (A) matches with (IV).
- (D) Dhrupad: The alap section of Dhrupad, an ancient and austere vocal style, is elaborated using meaningless syllables like 'nom', 'tom', 'ri', 'na'. This is known as Nom-Tom alap. So, (D) matches with (I).
- (C) Thumri: A semi-classical form. Towards the end of a Thumri presentation, the tabla often plays a fast, lively pattern called a 'Laggi' to which the singer responds. So, (C) matches with (II).
- (B) Prabhandh: An ancient compositional form described in musical treatises. One of its six constituent parts ('angas') is 'Tenak', which refers to the use of auspicious words or syllables. So, (B) matches with (III).
Step 3: Final Answer:
The correct matching is A-IV, B-III, C-II, D-I, which corresponds to option (D).