Explanation :
A microscope is used to see a large image of magnified objects. It can magnify up to an order of thousands. It works on the principle that when an object is placed beyond the focus of an objective lens, it forms a virtual, highly magnified image.
The image is formed at the least distance of distinct vision. It used two types of lenses i.e. an objective lens and an eyepiece.
So, the correct option is (D) " convex objective and eyepiece lenses ".