Reading Comprehension

Read the following passage and answer the question below. Mars has long captured human imagination as a potential destination for future exploration and even settlement, owing to its relative proximity to Earth and similarities in certain geological features. Since the 1960s, dozens of missions, including orbiters, landers, and rovers, have been sent to study the Martian surface, atmosphere, and potential for past or present life. Rovers such as Curiosity and Perseverance have discovered evidence suggesting that Mars once had liquid water flowing on its surface, raising the possibility that microbial life could have existed there billions of years ago. Current Martian conditions, however, are extremely hostile to life as we know it, with a thin atmosphere, freezing temperatures, and high levels of radiation due to the lack of a protective magnetic field. Space agencies and private companies alike are now developing plans for crewed missions to Mars, though significant technical and logistical challenges, including radiation exposure and the long journey time, remain to be solved. Question: What can be inferred from the passage about the challenges of sending humans to Mars?

• A. The journey time to Mars is very short
• B. All necessary technology has already been developed
• C. Significant technical and logistical challenges remain unsolved ✓
• D. Radiation exposure is not a concern for crewed missions