20. Which is a source of energy for Earth's living things?
I. trophic energy
II. sunlight
III. chemical energy
(A) I only
(B) II only
(C) I and II only
(D) II and III only

D

Trophic is technically Chemical and Sunlight energy

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.