How does the number and variability of fatty acids in sphingolipids compare to glycerolipids?

Sphingolipids have two variable fatty acids, while glycerolipids have one.

Sphingolipids have no variable fatty acids, while glycerolipids have one.

Both sphingolipids and glycerolipids have the same number of variable fatty acids.

Sphingolipids have one variable fatty acid, while glycerolipids have two variable fatty acids.