These lines (there is four of them) are residuals of the fusion of the five sacrum vertebrae that are fused. These "vertebrae" or segments present a characteristics, being the first of them very similar to a lumbar vertebra, large, and the other vertebrae are<span> progressively smaller and flattened. They also present a curved shape being anteriorly concave.</span>
bt bb bz bz bs bs db h bj bg
Explanation:
hajans
Answer:
D. Through radio telescopes
Explanation:
The way we are able to detect them is by radio telescopes