Daily Quiz 20 August 2025

Answer: a

Explanation:

• Statement 1 is correct:
  GPc is based on zinc-phthalocyanine, a compound that works with near-infrared (NIR) light, enabling non-invasive tumour imaging via photoacoustic imaging, which uses light and sound—not ionizing radiation.
• Statement 2 is correct:
  GPc is designed to be cost-effective, potentially replacing PET/MRI scans in detecting tumours, especially in low-income settings.
• Statement 3 is incorrect:
  GPc is a diagnostic agent, not a therapeutic one. It does not destroy cancer cells; it only helps in locating them.

Explanation:
• Statement 1 is incorrect: The trade deficit with China rose to $85 billion, Russia to $57.2 billion, Korea to $14.71 billion and Hong Kong to $12.2 billion in 2023-24 against $83.2 billion, $43 billion, $14.57 billion and $8.38 billion, respectively, in 2022-23. America is one of the few countries with which India has a trade surplus. The surplus is also there with the U.K., Belgium, Italy, France and Ban-gladesh.
• Statement 2 is incorrect: China has emerged as India’s largest trading partner with $118.4 billion of two-way commerce in 2023-24, edging past the U.S. The US was the top trading partner of New Delhi during 2021-22 and 2022-23.
• Statement 3 is correct: India has a free trade agreement with four of its top trading partners – Singapore, the UAE, Korea and Indonesia (as part of the Asian bloc).
• Statement 4 is incorrect: India’s total trade deficit in the last fiscal narrowed to $238.3 billion as against $264.9 billion in the previous fiscal.

Answer: (b)

Explanation:
EDE (Envelope Dimer Epitope)-like antibodies target conserved parts of the dengue virus envelope protein, providing immunity across all four serotypes, which is crucial for a universal vaccine. This is significant as earlier immunity sometimes worsened disease (antibody-dependent enhancement), which is option (a). Option (c) is incorrect because these antibodies develop naturally after exposure. Option (d) contradicts their broad neutralisation capability.

Answer: B

Explanation:

• Statement 1: Incorrect.
  A Vostro account is an account that a domestic bank holds on behalf of a foreign bank in the domestic currency (e.g., INR in India). The statement incorrectly describes it as an account held by a foreign bank in foreign currency. The correct understanding is that a Vostro account is maintained by the domestic bank for the foreign bank to handle transactions in the domestic currency.
• Statement 2: Correct.
  Vostro accounts allow foreign banks to hold and transact funds in the domestic currency, which reduces the need for frequent forex conversions. This helps reduce pressure on a country’s foreign exchange reserves because transactions can settle in the local currency rather than foreign currencies like the USD. Additionally, by facilitating settlements in domestic currency, Vostro accounts promote the use of that currency (e.g., INR) in international trade.
• Statement 3: Correct.
  In India, the Reserve Bank of India (RBI) issues operational guidelines concerning the functioning of Vostro accounts. The Ministry of Finance does not directly regulate these accounts. This distinction matters for regulatory and policy clarity.

Answer: D

Explanation:

• Statement 1: Correct.
  The muon is a fundamental particle in the lepton family, like the electron. It has similar properties such as electric charge and spin but is approximately 207 times heavier. This higher mass makes it sensitive to interactions with potential new particles and forces.
• Statement 2: Correct.
  The ‘g’ factor is a dimensionless number describing the magnetic moment of a particle relative to its spin. Theoretical quantum mechanics predicts a value of exactly 2 for an ideal point-like particle without other interactions. The actual measured value can deviate due to quantum effects.
• Statement 3: Correct.
  Because the muon interacts with “virtual particles” constantly popping in and out of existence, its magnetic moment (g) slightly differs from 2. If experiments observe a discrepancy between measured and predicted values, it may point to unknown particles or forces beyond the current Standard Model of particle physics, making the Muon g-2 experiment a probe for new physics.