Explanation:

A contract can be discharged in several ways. The correct answer is option 'D', which states that a contract can be discharged by mutual agreement and performance, lapse of time, operation of law, and breach of contract. Let's discuss each of these ways in detail:

1. Mutual Agreement and Performance:
- A contract can be discharged when both parties agree to end the contract. This is known as mutual agreement.
- Another way a contract can be discharged is through performance, which means both parties have fulfilled their obligations as per the terms of the contract.

2. Lapse of Time:
- A contract may have a specific duration or a time limit within which it must be performed.
- If the contract is not performed within the specified time frame, it is considered discharged by lapse of time.

3. Operation of Law:
- Certain events or circumstances can discharge a contract by operation of law.
- For example, if a contract becomes impossible to perform due to an unforeseen event, such as a natural disaster or death of a party, the contract may be discharged by operation of law.
- In some cases, a change in the law may render the contract illegal or unenforceable, leading to its discharge.

4. Breach of Contract:
- If one party fails to fulfill their obligations under the contract without a valid excuse, it is considered a breach of contract.
- The non-breaching party may choose to discharge the contract and seek remedies for the breach, such as damages or specific performance.

Conclusion:
A contract can be discharged by mutual agreement and performance, lapse of time, operation of law, and breach of contract. These are the various ways in which a contract can come to an end. It is important for parties to understand the circumstances under which a contract can be discharged to ensure their rights and obligations are properly fulfilled.