Many sprites or One Sprite with many animations?

I am building a mobile game which will use around 20 track pieces to form a layout. (Not all will be used on every track, but I have drawn 20 pieces will I'll use to generate some tracks).

I have decided to make the tracks look 3D even though the player will only interact with it in 2d. (Will achieve this by putting the collision polygon in the middle of the sprite.)

Does anyone know if either way below is more memory efficient than the other, taking into account this is for Android.

1) 20 Sprites

2) 1 Sprite with 20 animations, set to the correct track type.

Cheers

As far as I know, a sprite is generated by a single draw call - if you make 20 different draw calls on 20 different objects or 20 different draw calls through animations doesnt change something. Maybe think about using tilemaps, depending on if it *has* to be a sprite.

Reference: https://www.scirra.com/manual/134/performance-tips (scroll to "Using Sprites instead of Tiled Backgrounds")