Ana is planning to build an electrical circuit. before building it, she writes the statement, "if four batteries are connected to a light bulb, then the light bulb will burn longer than if two batteries are connected because more batteries provide more energy."

which best explains why ana's statement is a hypothesis rather than a theory?

A hypothesis is a reasonable guess based on something that you observe in the natural world.

A theory is a combination of multiple hypothesis which are tested nd retested again and again.

Ana's statement is a hypothesis because it is a statement of common sense but it has not been tested by Ana yet and there could be multiple different results and thus it is not a theory.

For example, More batteries do provide more energy but if all the batteries are providing energy at the same time the life of bulb will not be effected.

It is observed that Batteries connected in series to a bulb increases voltage and hence, brighter bulb while connecting batteries in parallel with the bulb will increase the overall battery capacity.  

i would think form in reponse to tensional forces