Answer:

The correct answer is option 'A', Russia. India is procuring a sizable number of AK-103 series of assault rifles for the Indian Army as part of the mega infantry modernisation programme.

Background:
The Indian Army has been in the process of modernizing its infantry weapons and equipment to enhance its combat capabilities. One of the key components of this modernization program is the procurement of new assault rifles to replace the outdated INSAS (Indian Small Arms System) rifles. The AK-103 series of assault rifles, manufactured by Kalashnikov Concern in Russia, has been selected for this purpose.

Reasons for Procuring AK-103:

1. Reliability: The AK-103 series of assault rifles are known for their robustness and reliability. They have a long history of service in various armed forces around the world, including the Russian military. The rifles have proven to be highly reliable even in challenging environments and adverse conditions.

2. Compatibility: The AK-103 rifles are compatible with the existing infrastructure and ammunition stockpiles of the Indian Army. This reduces the logistical challenges associated with the integration of new weapons into the armed forces.

3. Firepower: The AK-103 rifles are chambered for the 7.62x39mm cartridge, which provides superior stopping power compared to the 5.56x45mm cartridge used in the INSAS rifles. This gives Indian soldiers a significant advantage in combat situations, especially in engagements at longer ranges.

4. Cost-effectiveness: The AK-103 rifles offer a cost-effective solution for the Indian Army's modernization program. The rifles are manufactured in large quantities and have a proven track record, which helps in reducing the overall procurement cost.

5. Indigenous Production: In addition to the procurement of rifles from Russia, India has also signed an agreement with Russia to manufacture the AK-103 rifles domestically under a joint venture. This will not only fulfill the immediate requirements of the Indian Army but also provide a boost to the indigenous defense manufacturing industry.

Conclusion:
The procurement of AK-103 series assault rifles from Russia is a significant step towards the modernization of the Indian Army's infantry weapons. These rifles provide reliability, compatibility, firepower, and cost-effectiveness, making them a suitable choice for the Indian Army's requirements. Additionally, the joint venture for indigenous production will contribute to the 'Make in India' initiative and strengthen the domestic defense manufacturing capabilities.