Variation in which of the following lead(s) to variations in climate and vegetation? 

A)  latitude and altitude 
B)  altitude only 
C)  latitude and longitude 
D)  latitude only

Latitude and altitude have the greatest impact on climate and vegetation. Latitude affects temperature, with areas near the equator being warmer than areas near the poles, while altitude affects temperature and precipitation, with areas at higher elevations being cooler and receiving more precipitation than areas at lower elevations. These factors play a significant role in determining the types of plants and animals that can thrive in a given area. Longitude does not have a direct impact on climate and vegetation as it only indicates the east-west location of a place.