Willingness to marry is often expressed through various means, such as a proposal, request, or declaration. However, the most suitable answer for what is made about the willingness to marry is option 'C' - Declaration.

Explanation:
- When someone declares their willingness to marry, they are openly expressing their desire to enter into a marriage. This declaration can take many forms, including verbal statements, written letters, or even public announcements.
- Declarations of willingness to marry are often made by one individual to another, typically by the person who wishes to propose marriage. It is a formal and straightforward way of expressing their intentions and desires.
- Unlike a proposal or request, a declaration does not seek approval or consent from the other party. It is a statement of personal intent, indicating that the person is ready and willing to enter into a marital relationship.
- Declarations of willingness to marry can be made in various settings and contexts. They can be private, such as in a personal conversation or letter, or they can be public, such as during a public event or ceremony.
- The act of making a declaration signifies a certain level of commitment and seriousness in the intent to marry. It allows both parties to understand the other person's feelings and intentions clearly.
- Declarations of willingness to marry are often accompanied by expressions of love, commitment, and future plans. They serve as a starting point for further discussions and negotiations regarding the terms and conditions of the marriage.
- It is important to note that a declaration of willingness to marry does not guarantee a successful marriage. It is merely the initial step in the process of entering into a marital relationship, and further discussions and agreements are necessary for a marriage to take place.

In conclusion, while proposals and requests are also commonly associated with the willingness to marry, the most suitable answer to what is made about the willingness to marry is option 'C' - Declaration. Declarations serve as a clear and direct expression of one's intent to marry, without seeking approval or consent from the other party.