136k views
23 votes
Which of the following organisms have existed on Earth for the longest period of time?

O single-celled organisms
O multicellular organisms
O dinosaurs
O mammals

User Killogre
by
7.1k points

2 Answers

9 votes

Answer:

cyanobacteria.. single celled organisms

User Gionni
by
7.9k points
12 votes

Answer:

single-celled organisms

Step-by-step explanation:

User Rexroxm
by
7.5k points