Explanation:

The fundamental right to equality is enshrined in Article 14 of the Indian Constitution. It ensures that every citizen is treated equally before the law and has equal protection and equal opportunity under the law. However, economic equality is not explicitly included in the fundamental right to equality. Let's break down the different aspects of the fundamental right to equality mentioned in the options:

a) Equality before the law:
- This principle ensures that every individual, irrespective of their caste, religion, gender, or any other social factor, is equal before the law.
- It means that no person can be discriminated against or given special privileges based on their social or economic status.
- This principle promotes the idea that all citizens are subject to the same laws and should be treated equally by the legal system.

b) Social equality:
- Social equality refers to the absence of discrimination and prejudices based on social factors such as caste, religion, race, gender, or place of birth.
- It ensures that all individuals have equal status, opportunities, and rights in society.
- Social equality aims to eliminate social inequalities and create a just and inclusive society.

c) Equality of opportunity:
- Equality of opportunity ensures that all individuals have equal access to opportunities, resources, and facilities.
- It prohibits discrimination in areas such as education, employment, and public services.
- This principle promotes meritocracy and aims to create a level playing field for all citizens.

d) Economic equality:
- Economic equality refers to the equal distribution of income, wealth, and resources among individuals in society.
- It implies that there should be no significant disparities in economic conditions between different sections of society.
- However, economic equality is not explicitly mentioned in the fundamental right to equality in the Indian Constitution.

Therefore, the correct answer is option 'D' - Economic equality. The fundamental right to equality ensures equality before the law, social equality, and equality of opportunity, but it does not guarantee economic equality.