Answer:
Two ureters.
These narrow tubes carry urine from the kidneys to the bladder. Muscles in the ureter walls continually tighten and relax forcing urine downward, away from the kidneys. If urine backs up, or is allowed to stand still, a kidney infection can develop.
Explanation:
<em>It involves making observations, formulating a hypothesis, and conducting scientific experiments. Scientific inquiry starts with an observation followed by the formulation of a question about what has been observed.</em>
<em>Hope this helps</em>
<em></em>
<em>Please give me brainliest</em>
<em></em>
<em>Thank you for letting me answer your question </em>
<em></em>
<em>Thank you,</em>
<em>Florida Mermaid</em>
I would go for D or A! :)
