Step 1: Understand the conditions for life.
The conditions necessary for life include water, a stable atmosphere, and moderate temperatures.
Step 2: Review the options.
- Mars is the most likely planet to have conditions suitable for life, as evidence of water and a potentially habitable environment has been found.
- Mercury is too hot and lacks an atmosphere to support life.
- Venus has extreme temperatures and a thick toxic atmosphere, making it unlikely for life.
- Jupiter is a gas giant with no solid surface, making it unsuitable for life.
Step 3: Conclude.
Mars has the most potential for life, making option (A) the correct answer.
Final Answer:
\[
\boxed{\text{Mars}}
\]