Mi primera publicacion Margarita Mancia, Phonetics_and_Phonology_Album | Page 16

 Complementary allophones; they are instances where a specific allophone must be selected
to avoid confusion or make the speaker sound native. In this case, each allophone must be
used in a specific phonetic context.
 Free variation allophones: they can be freely selected based on personal preference.
Phoneme
/t/
Allophones
[t] [tʰ] [ʔ] [r]