What three conditions did the earliest bacteria need for energy production?

Light, water, and carbon dioxide

Explanation:

Bacteria are the oldest beings on Earth and are present almost everywhere - air, water, soil, air, dust and even volcanoes; and for that reason they are considered the most abundant living beings on the planet. Many people believe that bacteria only cause disease, but there are many bacteria that are used by man for beneficial things like lactobacilli, for example.

The first bacteria were very important for creating the atmosphere we know. These bacteria produced energy through light, water and carbon dioxide.

Oxygen (O2) concerntration

Temperature

pH