Mars May Have Been More Earth-Like in the Past Because

question 54

Multiple Choice

Mars may have been more Earth-like in the past because

• A) its atmosphere was thicker
• B) it was rotating more rapidly
• C) the Sun was dimmer, putting out less solar radiation
• D) it was not as close to the Sun

---

Definitions:

Reproductive Success

The extent to which an organism passes its genes to the next generation, often measured by the number of offspring that survive to reproduce.

Lever

A rigid bar resting on a pivot, used to help move a heavy or firmly fixed load with one end when pressure is applied to the other.

Food Pellet

A compressed unit of food, often used in animal feeding, which is designed for easy storage, handling, and consumption.

Conditioning

A process of behavioral modification by which a subject comes to associate a desired behavior with a previously unrelated stimulus.