How does secondary endosymbiosis explain the origin of chlorarachniophytes?

• A. Chlorarachniophytes acquired plastids from engulfing a green alga.
• B. Chlorarachniophytes developed from the direct fusion of two prokaryotic cells.
• C. Chlorarachniophytes originated through primary endosymbiosis with mitochondria.
• D. Chlorarachniophytes acquired nuclei through secondary endosymbiosis.

Answer: (A)