Explanation:
Azeotropes are binary mixtures that have a constant boiling point and composition. They form when the vapor and liquid phases of the mixture have the same composition, resulting in a maximum or minimum boiling point for the mixture.

A minimum boiling azeotrope is formed when the mixture has a lower boiling point than either of its components. This occurs when there is a strong positive deviation from Raoult's law, which states that the vapor pressure of an ideal mixture is equal to the sum of the vapor pressures of its components. In a positive deviation, the vapor pressure of the mixture is higher than predicted by Raoult's law.

Causes of Positive Deviation:
Positive deviations occur when the intermolecular forces between the molecules of the components are weaker than the forces between like molecules. This means that the molecules of the components prefer to stay together rather than mix with each other. As a result, the vapor pressure of the mixture is higher than predicted because more of the lower boiling component escapes into the vapor phase.

Effect on Boiling Point:
In the case of a minimum boiling azeotrope, the positive deviation from Raoult's law results in a lower boiling point for the mixture compared to its components. This is because the vapor pressure of the mixture is higher, meaning that it will boil at a lower temperature to achieve the same vapor pressure as the individual components.

Conclusion:
Therefore, a minimum boiling azeotrope is characterized by a large positive deviation from Raoult's law, leading to a lower boiling point for the mixture. Option 'A' is the correct answer.