Answer:
The correct answer is energy. Other organisms are not necessary, just like offsprings since there are many organisms that never have offsprings. Light is also not necessary with numerous organisms, especially those like the ones that live deep in the sea where light never reaches. Some form of energy is necessary for everyone.
A traveling clot that suddenly blocks a blood vessel is an embolism
A ph of 5 is acidic because anything lower than a ph of 7 is considered acidic anything above ph 7 is basic
