What observation led researchers to propose that chloroplasts evolved from cyanobacteria? a) both produce proteins. b) both contain mitochondria. c) both provide structure to cells. d) both perform photosynthesis.

D) Both Perform Photosynthesis

Chloroplast are specialized structures in plant and algal cells. The main function of the chloroplast is to perform photosynthesis by capturing the sunlight with the help chlorophyll pigments and convert it into energy storage molecules called as ATP.

Cyanobacteria are known to be the ancestor of chloroplast, the are also known as blue green algae because of the presence of photosynthetic pigments in it.

Although, Cyanobacteria comes under bacteria but they are capable of trapping the sunlight and produce energy. That shows ancestral relationship between chloroplast and cyanobacteria.

what's the question ?

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.