Which country announced a new satellite system named Marathon to support Internet of Things (IoT) connectivity and related services?

Introduction / Context:
This question belongs to current affairs and science and technology. It refers to the Internet of Things, commonly known as IoT, and asks about a country that planned a satellite system named Marathon to support such connectivity. IoT involves connecting devices, sensors and machines so that they can communicate and exchange data, often over satellite networks when ground infrastructure is limited.

Given Data / Assumptions:

• The satellite system is called Marathon.
• Its stated purpose is to support Internet of Things connectivity and services.
• We need to identify the country that announced this satellite system.
• The options include several major spacefaring nations.

Concept / Approach:
To solve this question, we recall recent technological news related to space programmes and IoT. Russia has announced a satellite constellation project named Marathon, intended to form part of a wider system providing low power communication links for IoT devices. While China, India, Japan and South Korea all have strong space agencies and communication satellites, the specific project name Marathon is associated with Russian plans rather than theirs.

Step-by-Step Solution:
Step 1: Note the unique keyword in the question, which is the satellite system name Marathon. Step 2: Recall which country has discussed a Marathon satellite constellation for IoT and navigation augmentation. Step 3: Recognise that Russian space authorities have outlined plans for the Marathon system as part of their broader navigation and communication efforts. Step 4: Compare this with China, India, Japan and South Korea, which are better known for other named systems such as BeiDou, NavIC, QZSS and regional communication satellites. Step 5: Since Marathon is linked with the Russian space programme, select Russia as the answer.

Verification / Alternative check:
You can verify the answer by checking summaries of major satellite constellations being developed around the time referenced in the question. Sources on Russian space projects mention Marathon as a system designed to support low power data links, including applications for Internet of Things, asset tracking and remote monitoring. No similar references assign this exact name to a Chinese, Indian, Japanese or South Korean system, which confirms the identification of Russia.

Why Other Options Are Wrong:
China has developed the BeiDou navigation system and various communication constellations, but Marathon is not one of its official programme names. India focuses on systems such as NavIC for navigation and different communication satellites under the INSAT and GSAT series, but not Marathon. Japan operates QZSS and other satellites, again with different names and goals than the Marathon system described. South Korea has growing satellite ambitions but is not associated with a constellation officially titled Marathon for IoT.

Common Pitfalls:
Because many countries now invest in satellite systems, students sometimes choose a well known space power like China or India by habit, without paying attention to specific project names. Another mistake is to assume that any advanced economy could randomly fit, but competitive exam questions usually rely on identifiable factual associations. Matching the name Marathon to Russia avoids these errors.

Final Answer:
The country that announced the Marathon satellite system for IoT services is Russia.