The correct option is C thylakoids
Chlorophyll a, chlorophyll b, xanthophyll, and carotenoids are various pigments involved in photosynthesis. These pigments are part of the photosystems and are present in the chloroplast of plants. Chloroplasts are covered by a dual membrane. Disc-like structures present in the cytoplasm of the chloroplast are known as thylakoids. These thylakoids are stacked upon one another and form the granum. The photosystems present in the thylakoid membrane of the chloroplast are responsible for the light-dependent reactions. Thus, chlorophyll is located within the thylakoid membrane.
Stroma is the homogenous matrix that contains grana.
The space between the two covering membranes (inner and outer) of the chloroplast is called intermembrane space.
The connection between two grana in a chloroplast is called stroma lamellae.