The correct answer is: (A) An Atmosphere
Explanation:
The atmosphere of Venus is almost ninety times denser than that of Earth. Due to Venus' denser atmosphere and chemical composition (as its atmosphere comprises of over 96% of Carbon dioxide), it experience an immense greenhouse effect. That is why its surface temperature remains higher than 470°. At that very high temperature, it is impossible to have life on the surface of Venus.
... the angular tilt of the Earth's position on its axis relative to the sun
The difference between the above velocities is that they exist in opposite direction of each other. or it can be said that they are negative vectors of each other.