Which of the Following Accurately Describes the Use of Tree

Which of the following accurately describes the use of tree rings for studying past climates (dendroclimatology) ?

A) The age of trees can be determined by tree ring analysis. By establishing the age of long-lived trees, one can determine the climate conditions of the area the year the tree sprouted.
B) The width of annual tree rings indicates the climatic conditions; wider rings suggest favorable conditions, whereas narrower rings suggest harsher conditions.
C) Dendrochronology is primarily used in the tropical regions, where one can easily correlate a tree species' age with the climatic conditions there.
D) Because most trees only live 60 to 100 years, dendrochronology can only serve as a climate record for recent history and are primarily used to supplement instrument data.