The answer would be “D,” as gravity is the force that keep all objects on Earth’s surface.
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.
Cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.
(Hope this helps!!)
The correct option is this: PLANTS CAN BE USED TO MAKE MATERIALS.
Plants are very important living organisms and they can be used in diverse ways. Some plants can be used as foods, some plants are used as raw materials for making pharmaceutical drugs and other herbal products. Plants, such as cotton are used to make clothing materials and dead and decaying plants serves as fertilizer that add nutrients to the soil.
