What best summarizes the concept of natural selection?

Which of the following particles always has a positive charge? a. electronb. neutron c. proton d. ion

Aremote community desperately needs more electrical energy. it is located in an area with the following characteristics: average wind speed of 15 – 20 km/hr some medium-sized rivers with slow-moving currents few coal deposits some oil exploration being conducted within 400 miles based on the above information, which energy source would be the most economical and safest for the community to pursue? a. fossil fuel b. hydroelectric c. nuclear d. wind

What is a general feature of a species that varies from one individual to the next (skin tone,eye color or hair color)? a.organism b.trait c.character