Answer: A

Explanation:

Nebulae are vast clouds of gas and dust scattered throughout space, often serving as the birthplaces of stars.

Emission Nebulae: These nebulae emit light due to the ionisation of gases by nearby hot stars. Examples include the Orion Nebula and the Lagoon Nebula. Hence, pair 1 is correctly matched.

Reflection Nebulae: These nebulae shine by reflecting light from nearby stars, often appearing blue due to the scattering of starlight by dust particles. The Witch Head Nebula is a notable example. Hence, pair 2 is not correctly matched.

Planetary Nebulae: Formed when a dying star sheds its outer layers, planetary nebulae exhibit a variety of shapes and colours. The Helix Nebula and the Ring Nebula are well-known examples. Hence, pair 3 is not correctly matched.

Answer: C

Explanation:

Recently, it has been seen that the Fort Emmanuel situated at Fort Kochi Beach in Kochi, Kerala need for conservation. Fort Emmanuel was built along the Fort Kochi beachfront by the Portuguese in 1503. Hence, statement 1 is correct.

It served as a strategic bastion and symbolized the alliance between the Maharaja of Kochi and the Portuguese monarch. Most of Fort Emmanuel's walls and bastions were destroyed by the Dutch and later the British by 1806. Presently, remnants of the fort remain submerged along the coast, with occasional visibility during low tides. Hence, statement 2 is correct.

Situated from Bastion Bungalow (now a heritage museum) to the southern end of the beach, Fort Emmanuel holds historical importance for its role in colonial history and maritime trade. The construction of forts like Fort Emmanuel was part of the Portuguese strategy to protect their coastal colonies, including Fort Kochi, Goa, Kollam, Kozhikode and Kodungalloor. These forts were crucial for securing trade routes and repelling attacks from rival powers. Hence, statement 3 is correct.

Answer: D

Explanation:

Recently, it has been seen in the Chukkalapadu settlement of the Muria tribe in Andhra Pradesh's Alluri Sitarama Raju district, the tradition of the baby-father 'cradle bond' persists. The Muria tribe lives in the Bastar district of Chhattisgarh  and in the states of Telangana, Andhra Pradesh and Odisha. They speak Koya, a Dravidian language and has no caste system. Hence, statement 1 is correct.

This tribe is predominantly agrarian and cultivates rice. The Muria tribe mandates that a man must weave a bamboo cradle, called 'vookada,' for his newborn child as a lifetime memory. Traditionally, they follow a folk religion, worshipping nature and deities like Budhadev (Dev) of their villages and clans. They held ST status in Chattisgarh but they were not granted ST status in their migrated states such as Telangana. Hence, statement 2 is correct.

Answer: C

Explanation:

Recently, the BRS leader K.T. Rama Rao, who is under attack over phone tapping of politicians, has offered to undergo a polygraph test. A polygraph test, also known as a lie detector test, is a machine that records a person's physiological responses when they answer questions. Hence, statement 1 is correct.

During the test, instruments like cardio-cuffs or electrodes are attached to the person. The test measures and records things like blood pressure, pulse, respiration, and skin conductivity.  Polygraph tests are utilized for event-specific investigations, employee screenings and security screening to identify potential threats to national security. The Supreme Court invoked Article 20(3), protecting the Right against self-incrimination, stating that no accused can be forced to testify against themselves. Hence, statement 2 is incorrect.

In the case of D.K. Basu vs. State of West Bengal (1997), the Supreme Court ruled that subjecting individuals to involuntary polygraph and narco tests constitutes cruel, inhuman and degrading treatment, violating Article 21, the Right to Life and Liberty. Hence, statement 3 is correct.

Moreover, the Indian Evidence Act of 1871 does not accept the results of these tests as evidence. In 1999, the National Human Rights Commission adopted guidelines for administering the Polygraph Test, emphasizing aspects like consent and proper documentation of the test process. Hence, statement 4 is correct.

Answer: C

Explanation:

Cryogenics is the science of materials at temperatures below negative 153 degrees Celsius, where common gases like hydrogen and nitrogen become liquid. Helium and nitrogen are primary cryogenic fluids, with boiling points of negative 269 degrees Celsius and negative 196 degrees Celsius, respectively. Hence, statement 1 is correct.

Cryogenic hydrogen and oxygen are crucial rocket fuels, powering advanced rockets like ISRO's LVM-3. Cryogenic hardening enhances materials like steel, making them harder and stronger.  Cryogenic fluids are vital in Magnetic Resonance Imaging (MRI) devices for medical diagnostics. Refrigeration technology is utilized to achieve and maintain cryogenic temperatures required for various applications. It enables the use of materials and fuels in extreme conditions, facilitating advancements in space exploration, industry and medical diagnostics. Hence, statement 2 is correct.