Question

when did life on earth begin?
a about 4 to 8 billion years ago
b about 3.5 to 4 billion years ago
c about 1 to 3.5 billion years ago
d about 4.5 to 7 billion years ago
check it

Explanation:

Scientific evidence, such as fossilized microbial mats (stromatolites) and geochemical traces, indicates that the earliest life on Earth emerged between 3.5 and 4 billion years ago. Earth itself formed approximately 4.5 billion years ago, so the other options are either too early (predating Earth's formation) or too late.

Answer:

b. About 3.5 to 4 billion years ago