**Explanation:**

**a) Rights are reasonable claims of persons recognized by society and sanctioned by law:**
Rights are reasonable claims that individuals have, which are recognized by society and sanctioned by law. They are based on the principles of fairness, justice, and human dignity. Rights are not arbitrary or subjective; they are grounded in moral and legal principles that society has agreed upon. These principles are usually enshrined in a country's constitution or in international human rights treaties.

Rights are considered reasonable claims because they are based on the idea that all individuals have inherent worth and should be treated with respect and dignity. They are not based on personal preferences or desires, but on fundamental principles of equality and justice.

**b) It is only recognized by the state government:**
This statement is not correct. While it is true that the state government plays a crucial role in recognizing and protecting rights, rights are not solely recognized by the state government. Rights can also be recognized by international bodies, such as the United Nations, or by civil society organizations. In fact, many human rights are recognized and protected at the international level, regardless of whether they are recognized by a specific state government.

**c) A person can only claim in a court of law:**
This statement is also incorrect. While a person may choose to seek legal recourse in order to protect and enforce their rights, rights can be claimed and exercised in various ways, not just in a court of law. For example, individuals can exercise their right to freedom of speech by expressing their opinions openly and freely, without needing to go to court. Similarly, individuals can exercise their right to education by attending school or pursuing lifelong learning opportunities, without needing to file a lawsuit.

**d) All the above:**
Since statements b) and c) are incorrect, the correct answer is a) - rights are reasonable claims of persons recognized by society and sanctioned by law. This statement accurately captures the essence of what rights are - they are reasonable claims that individuals have, which are recognized and protected by society and the law.