Explanation:

- Venus and Mars both have thin atmospheres dominated by carbon dioxide.

- Option 1: 45-47% – This percentage is lower than the actual carbon dioxide levels on Venus and Mars.

- Option 2: 52-55% – This is also an underestimate of the carbon dioxide content for these planets.

- Option 3: 74-77% – Another underestimate; while high, it's not quite enough.

- Option 4: 95-97% – This is the correct range for both planets.

- The atmosphere of Venus is roughly 96.5% CO2.

- Mars has an atmosphere that is about 95% CO2.