Plant-deer-tiger

The first step in the energy chain that created the bonds of proteins in the tiger's muscle cells in the food chain shown above is

A. deer the tiger ate
B. plant the deer ate
C. photons the sun made
D. carbohydrates the plant made

I think its A because by eating the deer the tiger gets proteins in his body?

3 answers

Is that the first step in this food chain?
No,how would the photons from sun provide the tiger with proteins in his body?
http://www.bio.miami.edu/ecosummer/lectures/lec_foodweb.html