Answer:i found this on google and got it right
Explanation:
Image result for What is the difference between spindle fibers and spindle microtubules
Spindle fibers are used in cell division, and are made of microtubules. ... As the others have written, microtubules are a “track” that can move organelles around when “motor” proteins (that cleave ATP) pull those organelles. The spindle is what moves the chromosomes during mitosis and meiosis
C. cell membrane the cell membrane lets the good stuff in and keeps the bad stuff out.
The dead organisms are recycled back by the activity of decomposing or decomposition. I hope this helps!
Both A, B, and C are found in the excretory system.
Myofibrils are in the muscle of the intestines, villi increase surface area of the intestine, and nephrons help to filter in the kidney. Osteoblasts are found in bone, so therefore is not part of the excretory system