Ok your thyroid gland also contains selenium
Microscopes have been used for centuries in order to see specimen scientists cannot see with their unaided eye. Antón VanLeeonhoeuk is given credit for designing the first lenses for microscopes in the 16th century. He looked at “animacules” which we would now call bacteria and protists. Robert Hooke first coined the term cell, as he looked at cork and thought it looked like cells that monks slept in. Improvements were made in the following centuries, and Ernest Leintz in the 1800s creates a way to have differing magnification lenses on one microscope. Continuing into the 1900s and 2000s there are now electron scanning microscopes, ultraviolet microscopes, atomic force microscopes, and electron tunneling microscopes—all which allow scientists to have better resolution and to see smaller and smaller things. Microscope technology will continue to improve as scientists discover more ways to magnify the microscopic world.
If the predator that feeds off the dart frogs goes extinct or migrates to a different area then the dart fronts will have a much larger population. This means that the resources the dart frogs rely on will start to deminish and their prey will have smaller numbers
B is the answer if not B then C
