Most of today’s hydrogen is produced from natural gas through a process called steam methane reforming.This is where steam and（）come together under high temperature to produce hydrogen.

Most of today’s hydrogen is produced from natural gas through a process called steam methane reforming.This is where steam and（）come together under high temperature to produce hydrogen.
A.water
B.hydrocarbons
C.oxygen
D.methane
正确答案：hydrocarbons