The Ladies crew neck shirts come in 3 different brands.  All have a nice relaxed neck that will not choke you.  All are soft and have a relaxed fit.

The Black and Military Green are Bella + Canvas Relaxed Jersey Tee, 100% cotton.

Athletic Blue, Lilac and Seafoam are a tri-blend from Tultex.  The blend is cotton, poly, rayon and are thin and super soft.  These are more fitted than the others.

Plum Rose is a Gildan softstyle 100% cotton shirt.

Silk Coral and Tropical Blue are also Gilden but they are the "Heavy Cotton".  They are 100% cotton and IRL they are much brighter than in the images.