Which of the following describes lineation?

A) May be due to elongated mineral crystals that grow in linear orientation.
B) Stretched-out mineral crystals may show lineation.
C) Can form under ductile shearing.
D) All of these describe lineation.

Lineation in geology refers to any linear feature observed in rocks, often resulting from the parallel alignment of mineral grains or structural features within the rock. This can occur through processes such as the elongation of minerals during metamorphism, where minerals grow in a preferred orientation under differential stress, or due to ductile shearing where rocks are deformed under conditions that allow them to stretch and flow. Therefore, all the given options accurately describe aspects of how lineation can form.