Which nation announced an ambitious plan to build the first human city on Mars by the year 2117?

Introduction / Context:
Space exploration is increasingly becoming a field of international competition and cooperation. Some countries have set very long term goals, including building permanent human settlements on other planets. The plan to build the first city on Mars by 2117 attracted global attention and is an important fact for current affairs and science awareness questions.

Given Data / Assumptions:

- The project mentioned is to build the first city on Mars.

- The target year mentioned is 2117.

- The options list four nations: India, United Arab Emirates, China and Russia.

- We must identify which country officially announced this futuristic plan.

Concept / Approach:
The United Arab Emirates, through its leadership, announced the Mars 2117 project. This long term initiative aims to develop scientific capabilities and international partnerships that could eventually support a human settlement on Mars over the next hundred years. The announcement followed the country broader interest in space, including missions to Mars orbit. Recognising that the phrase first city on Mars by 2117 is associated with the United Arab Emirates is the key to solving this question.

Step-by-Step Solution:
Step 1: Note the very long horizon year 2117 and the focus on a Mars city, not just a probe. Step 2: Recall which nation publicised a Mars 2117 project in recent years. Step 3: Connect this with news about the United Arab Emirates launching its own Mars mission and investing in space research. Step 4: Recognise that while China, Russia and India have ambitious space programmes, the specific branding Mars 2117 city is linked with the United Arab Emirates. Step 5: Select United Arab Emirates as the correct answer.

Verification / Alternative check:
If you remember headlines saying that the United Arab Emirates leadership unveiled a one hundred year plan to build a human city on Mars, then this memory directly confirms the correct answer. This was widely reported in technology and space news sections and discussed as part of the country vision to diversify beyond oil by investing heavily in science and innovation.

Why Other Options Are Wrong:

Option A (India) has conducted Mars Orbiter Mission but has not officially announced a Mars city plan fixed to the year 2117.

Option C (China) has strong lunar and Mars exploration goals but not this specific Mars 2117 city branding.

Option D (Russia) has a long history in space but is not associated with this particular long horizon Mars city announcement.

Common Pitfalls:
Candidates sometimes assume that only traditional space powers like the United States, Russia or China would make such bold announcements. However, newer players like the United Arab Emirates are also investing heavily in space. Another pitfall is focusing only on the word Mars and ignoring the distinctive year 2117, which is strongly tied to the UAE project in news coverage.

Final Answer:
The correct answer is United Arab Emirates, which announced the Mars 2117 project to build the first human city on Mars by the year 2117.