Concept:
The Mercator projection is a cylindrical conformal projection. While it is excellent for navigation, it creates significant areal distortion that increases toward the poles.
Step 1: Evaluating Statement A.
The primary strength of the Mercator projection is that it represents "Rhumb lines" (lines of constant bearing) as straight lines. This made it indispensable for maritime navigation (shipment) during the 19th century, which was the golden age of sail and steam. Thus, (A) is correct.
Step 2: Evaluating Statements B and C.
Because distortion increases toward the poles, high-latitude regions (where the British Empire and Europe are located) are shown larger than they actually are, not smaller. Conversely, tropical "colony countries" (which are near the equator) appear relatively smaller compared to the northern giants. Thus, (B) and (C) are incorrect.
Step 3: Evaluating Statement D.
The Mercator projection famously exaggerates polar areas. On a standard Mercator map, Greenland (approx. 2.1 million km$^2$) appears to be roughly the same size as or even larger than South America (approx. 17.8 million km$^2$), even though South America is actually 8 times larger. Thus, (D) is correct.