Match List-I with List-II

	List-I (Example)		List-II (Type of Solution)
A.	Humidity	I.	Solid in solid
B.	Alloys	II.	Liquid in gas
C.	Amalgams	III.	Solid in gas
D.	Smoke	IV.	Liquid in solid

Choose the correct answer from the options given below:

The correct option is A-II, B-I, C-IV, D-III.

A solution is a homogeneous mixture of two or more substances. Depending on the physical states of the solute (the substance being dissolved) and the solvent (the medium in which the solute is dissolved), solutions can be classified into various types:

1. Humidity (A matches with II):
Humidity represents water vapor present in the air. In this case, water droplets (liquid solute) are dispersed in air (gas solvent). Thus, it is a Liquid in gas type of solution.

2. Alloys (B matches with I):
Alloys (like brass or bronze) are homogeneous mixtures of two or more metals. Since both the solute and the solvent are in the solid state, it is a Solid in solid type of solution.

3. Amalgams (C matches with IV):
Amalgams are alloys containing mercury. Since mercury is a liquid at room temperature (liquid solute) and is mixed with a solid metal like sodium or silver (solid solvent), it constitutes a Liquid in solid type of solution.

4. Smoke (D matches with III):
Smoke consists of fine solid particles of soot, carbon, or ash suspended in the air (gas). Therefore, it is a Solid in gas type of solution.

Matching the lists gives:
A → II (Humidity - Liquid in gas)
B → I (Alloys - Solid in solid)
C → IV (Amalgams - Liquid in solid)
D → III (Smoke - Solid in gas)