Earth is composed of four main layers, starting with an inner core at the planet's center, enveloped by the outer core, mantle, and crust. The inner core is a solid sphere made of iron and nickel metals about 759 miles (1,221 kilometers) in radius.
source: nasa
it is impossible for a map projection to be accurate. the most common one is the mercator projection. Many projections have been tried but all very flawed. the most reliable form of a map is a globe but of course, it's not a projections...so.
The correct answer is : D. Pleistocene epoch
The Pleistocene epoch lasted from about 2,500,000 years ago to 11,700 years ago. In this era, a lot of repeated glaciations happened on earth, since most of Earth's geographical surface is covered in Ice.
The chronometer is a device to measure time in a period of time, therefore not a correct answer.