Question

In most ecosystems, the original source of energy for the living things in the system is __________.
a. the sun
b. the primary producer
c. glucose
d. the heterotrophic

Answer 1

Answer: The correct answer is Sun

Explanation:

Note that the ORIGINAL (i.e natural and ultimate) source of energy is the sun. The sun's energy, called Solar energy is then trapped by a pigment in primary producers called Chlorophyll to produce sugars (glucose) through the process of PHOTOSYNTHESIS.

Answer 2

The sun.
All the energy we get through the chain starts with the sun.