Does the Ability of Humans to Produce Synthetic Fertilizer Mean

Does the ability of humans to produce synthetic fertilizer mean that the carrying capacity of our biosphere for the human population is without limit?

A) Yes; with a constant supply of fertilizer humans can produce an unlimited amount of food.
B) No; the resources needed to produce fertilizers are themselves limited, as with other resources eventually fertilizer production will peak and decline.
C) Yes; fertilizers are almost entirely nitrogen, and as the most abundant gas in the atmosphere the supply of nitrogen is essentially unlimited.
D) No; converting the nitrogen in the atmosphere to a form chemically suitable for fertilizer is not economically practical.