all of the above
Algae process photosynthesis thru chloroplast which is a kind of plastid- a round oval disk-shaped body, that is involved in the synthesis and storage of food stuffs.
Chloroplasts are distinguished from other types of plastids by their green color which results from the presence of two pigments namely chlorophyll A and chlorophyll B.
A function of these pigments is to absorb light energy in plants for powering the process of photosynthesis.