Which name is given to the fluid enclosed by the chloroplast inner membrane around the grana?

1. Grana are the stacks of thylakoids inside a chloroplast. 2. They are bathed in the fluid enclosed by the chloroplast inner membrane. 3. That fluid is called the stroma. 4. The mitochondrial equivalent is called the matrix, so that term belongs to the other double-membrane organelle. 5. The chloroplast fluid is the stroma. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 4 "Cell Structure", section 4.3 Eukaryotic Cells_